Every morning starts with this smooth, sugar-free keto cold brew over ice — 0g net carbs and naturally low in acid. A fresh batch takes about five minutes of hands-on time, and I make one every week.
I drink cold brew every single morning. Not sometimes, not when I remember to prep it. Every morning. I keep a batch in the fridge at all times, pour it over ice with a big splash of heavy cream, and that's how my day starts. I've been making it this way for years, long before every coffee shop had a sugar-free option on the menu.
Here's what most people get wrong: they think this is just regular iced coffee that happens to be cold. It's not. Cold steeping extracts flavor differently. The result is smoother, naturally sweeter, and up to 67% less acidic than hot-brewed coffee poured over ice. If regular coffee bothers your stomach, switch to this.
My method is dead simple. I weigh out 85 grams of coarsely ground beans (not a volume scoop, the weight matters), add a liter of filtered water, and let it sit in the fridge for 18-24 hours. I tested different amounts over months before landing on 85g as the sweet spot for concentrate strength. Too little and it tastes watered down. Too much and it gets bitter no matter how long you steep.
What comes out is a concentrate. I dilute mine about 1:1 with water or pour it over a full glass of ice, which melts down to the right strength. Some mornings I go with heavy cream for a rich, low carb coffee that feels indulgent. Other times I blend it with ice and a little sweetener for something closer to a keto frappuccino.
The concentrate also works as a base for other drinks. I've used it in keto dalgona coffee, mixed it into a chocolate peanut butter smoothie for an afternoon pick-me-up, and poured it over dairy free ice cream as a quick affogato. One batch covers about a week, so I prep on Sundays and don't think about it again until the jar is empty.
For sweeteners, I use liquid monk fruit or powdered allulose. Both dissolve in cold liquid, which matters. Granulated erythritol sinks to the bottom and just sits there. If you only have granulated sweetener, dissolve it in a tiny bit of warm water first, then stir it in.
Grind size makes or breaks this recipe. You want coarse, roughly the texture of raw sugar. Fine grounds over-extract during that long steep and turn the whole batch bitter. If you don't have a grinder, buy pre-ground coffee labeled "coarse" or "French press grind."
If you're into coffee drinks, I have a whole collection worth trying: keto caramel macchiato, dalgona matcha latte, and frozen hot chocolate for when you want something completely different. Reader Amber D. said it better than I could: "No bitterness, no aftertaste, just smooth. I've kept a batch in the fridge every week since." That's exactly the result you're going for.
I weigh out 85 grams of beans on a scale before grinding them.
What to Stir Into Cold Brew
Heavy cream is not the only option. These all work stirred into cold brew:
macadamia nut milk
almond milk
coconut milk
sugar free chocolate syrup
sugar free caramel syrup
stevia or monk fruit
The longer the grounds steep the stronger the coffee gets, and I have let a batch go a little past 24 hours with no problem.
How to Strain the Grounds
If you used a cold brew maker, straining is easy. Just lift out the filter that holds the grounds. With the jar method, set a coffee filter inside a fine mesh sieve, or drape cheesecloth over the sieve, then pour the coffee through to catch the grounds.
I keep the finished cold brew in a glass jar in the fridge.
Grind beans using a food processor or coffee grinder.
2
Add coffee to brewer
If using a Cold Brew Coffee Brewer: Add ground coffee to the filter.
3
Pour water
Slowly pour water over the ground coffee to the max fill line on the carafe.
4
Add coffee to mason jar
If using a mason jar or pitcher: Add ground coffee to the bottom of the mason jar.
5
Add water
Add 1 liter of water to the mason jar.
6
Refrigerate overnight
Cover and let rest in the refrigerator overnight.
7
Strain the coffee
Strain the coffee through a fine-mesh sieve, cheesecloth or a coffee filter if using the mason jar method.
Nutrition
Per serving: 1 cup
Calories
2
Fat
0g
Protein
0.3g
Total carbs
0g
Net carbs
0g
Nutrition is an estimate calculated from the ingredients listed. Brands vary, so check labels if you track closely.
Frequently Asked Questions
How do I order this drink at Starbucks?
I order at Starbucks all the time. Ask for a Venti, no classic syrup (they add sweetener by default), and sub in heavy cream. In the app, just customize the drink and remove all syrups. The Nitro version is also great since it's naturally creamy from the nitrogen infusion. A grande Nitro is less than 1 net carb when you drink it black.
Can I make this with a French press?
I've done it plenty of times and it works perfectly. Add your coarse grounds to the French press, pour in cold water, and put the whole thing in the fridge for 18-24 hours. When it's ready, press the plunger down slowly. The built-in mesh filter does all the work. I still prefer a dedicated brewer because cleanup is easier, but a French press makes identical concentrate.
Can I freeze the concentrate?
I freeze mine into ice cube trays whenever I make too much. The frozen cubes are perfect for iced coffee because they don't water down the drink as they melt. I also toss them into smoothies for a caffeine boost. The concentrate keeps in the fridge for two weeks, so I usually don't need to freeze it, but it's a solid backup plan.
What is the difference between this and iced coffee?
I get asked this constantly. Iced coffee is regular hot-brewed coffee poured over ice. This method steeps grounds in cold water for 18-24 hours, which extracts flavor completely differently. The result is smoother, less bitter, and significantly less acidic. I can drink this black with zero discomfort, which I never could with regular iced coffee.
Can I drink this black while intermittent fasting?
I do it during my fasting window all the time. Black, with zero calories and zero carbs, it doesn't break a fast. The smooth, less acidic flavor actually makes it easier to drink black than regular coffee. I keep a jar in the fridge specifically for fasting mornings. Once my eating window opens, I add heavy cream for a richer, low carb version.
What coffee-to-water ratio makes the best concentrate?
I use 85 grams of coarsely ground beans to 1 liter of water. I landed on that ratio after testing different amounts for months. Stronger makes it too intense even when diluted, and weaker produces something that tastes like brown water. If you want to scale up, keep the same proportion: 85g per liter. I sometimes double it when I know the week is going to be busy.
Is this less acidic than hot coffee?
Noticeably, yes. I switched for exactly this reason. Cold steeping extracts fewer of the bitter, acidic compounds that hot water pulls out of coffee grounds. My stomach handles it so much better. I've seen research claiming up to 67% less acidity, and based on how I feel after a glass versus a regular cup, I believe it.
Can I make a vanilla sweet cream version at home?
I make my own vanilla sweet cream all the time. Whisk together heavy cream, a splash of vanilla extract, and a few drops of liquid monk fruit or a tablespoon of powdered allulose. Pour the concentrate over ice and float the sweet cream on top. It layers beautifully. I keep a small jar of the cream mix in my fridge so it's ready whenever I want it.
How much should I dilute the cold brew concentrate?
What you strain off is a concentrate, not a ready-to-drink coffee, so I never pour it straight. I cut mine about 1:1 with water, or I pour it over a full glass of ice and let the melt thin it down for me. The one time I drank it undiluted I was wired into the afternoon, so start with equal parts and adjust from there. When I want something richer I swap the water for a splash of heavy cream instead.
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Two calories a cup surprised me. Pouring the water in slow like you say really does matter. I dumped it in fast once and the grounds on top stayed dry, so it came out weak.
The mason jar method works but the strainer leaves grit in every glass. Running it through a paper coffee filter after the initial strain takes about 90 seconds and makes a real difference. I also started adding a thin strip of orange peel to the grounds before the water goes in. Knocks back the bitterness, and the coffee ends up balanced on its own. The 85-gram ratio runs mild if you’re used to drinking concentrate; I’ve settled on 100 grams and that’s finally where it tastes right to me. Honest note on the recipe. The method itself is solid, and once you find your ratio this just becomes the thing you make every Sunday.
I should add the paper filter pass to the post notes, I’ve gotten the grit question before. Orange peel in the grounds I’ve never done. I’m doing it this Sunday.
I showed up to my buddy’s Saturday brunch with a mason jar of this because I’d made too much that morning, and his wife took one look and said ‘oh nice, you brought La Colombe,’ which I just let happen. The one person in that group who is genuinely insufferable about his coffee, the guy who orders the expensive stuff every morning and will absolutely tell you about it, poured himself a second glass and said it tasted cleaner than what he normally drinks. That comment made me feel unreasonably good about a mason jar. I still haven’t told anyone it’s zero sugar because I think knowing would make them second-guess themselves, and watching that is honestly a little funny. All you need is the 85 gram ratio and about 20 hours in the fridge, which I keep having to explain because people assume it’s complicated. Going to start making bigger batches before I bring it anywhere.
Yep, decaf works exactly the same way. Cold brewing is just slow cold-water extraction, caffeine isn’t doing anything in the process. Same 18-24 hours, same result. I make a decaf batch sometimes when I want something at night.
Used 90 grams of beans instead of 85 because I like it on the stronger side, then just diluted with a splash of water or cream after steeping. Still came out smooth with zero bitterness, and the extra concentration means I can control the strength each morning without brewing a fresh batch. Mason jar method was a lot simpler than I expected for my first time making cold brew at home. Been pouring it over ice every day this week and it is genuinely the only thing getting me through this heat.
I had never made cold brew before and genuinely wasn’t sure I was doing it right. The grind size threw me off. The recipe doesn’t say how coarse to go, so I landed somewhere in the middle and hoped for the best. Turns out fine, but I was anxious the whole 18 hours. The coffee is so much smoother than anything I’ve bought at a store, and I drink a lot of iced coffee, so I’d know. Made it twice with the mason jar method now. Hooked. My one note: some guidance on grind size would really help beginners because that’s the part I still feel like I’m winging.
Coarse is right, like sea salt or coarser. Cold brew is forgiving on grind though (not like espresso or pour-over), so medium still works, it just steeps a bit darker. Adding grind guidance to the recipe.
Been making this every Saturday morning for a few months now, and I finally landed on the version that clicked. The recipe calls for 85 grams of beans, but I bumped it to around 100 and steeped the full 24 hours instead of the minimum. The concentrate comes out noticeably richer. Over ice with heavy cream it holds up way better than anything pre-made. I also switched from dark roast to medium roast a few weeks back, and it brought out something almost chocolatey in the finish. Didn’t expect that but really liked it. Cold brew always felt like a summer thing to me, but I’m drinking it year-round now. Sunday nights I set the mason jar up before bed and it’s ready to pour by Monday morning.
I’ve tried every cold brew bag on the market and a couple DIY methods before I found this. The 85 grams to 1 liter ratio is the first that actually tastes like real cold brew instead of watered-down iced coffee. What got me was the acid. I’ve had to cut back on my morning coffee because my stomach can’t handle it, and this one doesn’t do that thing where you feel it two hours later. Five minutes, no special equipment. Docking a star because I rushed the grind the first time (food processor too fine), so pay attention to that step. But when you get it right, this is freaking better than anything premade, and it costs almost nothing.
The acid is the whole reason I switched to cold brew at home. Hot coffee had my stomach wrecked by mid-morning. Food processor is always too fine, that one’s on the equipment not you.
My husband is the most particular person about his coffee (we’re talking a whole setup with a scale and a gooseneck kettle) and I made this mostly just for myself. He tried a sip to be polite and now we go through a full liter every four days. I’ve started grinding a bigger batch on Sundays just to keep up with him.
Switched from a fine grind to coarse on a whim and the bitterness I kept getting was just gone. Same 85 grams, same steep time, totally different cup. If your batch tastes sharp, try going coarser before you write off the recipe.
Fine grinds over-extract in cold water too, just slower. Same 85 grams but way more surface area, so the extraction curve is totally different by hour 20. Added a grind note to the recipe after Tricia ran into the same thing.
Smooth and completely acid-free like promised, though I wish there was a note on grind size since mine came out weak the first time until I landed on a coarser grind.
Just made cold brew at home for the first time and I’m annoyed at every dollar I spent on the bottled stuff. Steeped overnight in a mason jar, came out way smoother and less acidic than I expected. Does dark roast vs medium roast make much difference, or is it all about steep time?
Roast makes a bigger difference than people think. Dark gets you that chocolatey, low-brightness cup – I usually land on medium-dark. Steep time is your concentration dial, not your flavor dial.
My wife has refused to touch my morning coffee for years but poured herself a glass of this over ice this morning and said nothing, just nodded, which from her is basically a standing ovation. Something about the low acid maybe, but she’s been hovering around the mason jar I keep in the fridge all week.
A silent nod from someone who’s refused your coffee for years counts. She’s right about the acid – cold steeping pulls fewer of the bitter compounds than hot water does. My stomach noticed the difference the first week I switched.
