I am trying to make thick hot chocolate. At first I used cocoa powder and cornstarch as the thickener, bringing the milk + cocoa powder + sugar mixture to a boil. It worked but it always tasted burnt (not sure if that was the milk or cocoa) and the cocoa seemed to clump up.

Now I'm using bars of unsweetened chocolate. I melt them over a double-boiler and then add the milk. When I do this the melted chocolate instantly becomes granular and the drink has a sandy, gritty texture. The flavor is excellent (very dark compared to the bland cocoa powder) but I want the drink to be smooth and thick.

Any ideas?

PS A scientific explanation of this would be much appreciated. I like understanding what is happening in my cooking.

  • Granularity with addition of liquid is "seizing" of the chocolate. cooking.stackexchange.com/questions/1854/… Boiling should never happen unless you do love the burnt taste. Whisking and time may help with the seized texture, but I can't even imagine wanting to put cornstarch in hot chocolate...
    – Ecnerwal
    Commented Nov 28, 2016 at 17:24
  • @Ecnerwal Thanks, I will read about seizing. I got the cornstarch idea from this recipe: allrecipes.com/recipe/216167/…
    – user52037
    Commented Nov 28, 2016 at 17:30

3 Answers 3


Your chocolate is seizing. There's a nice discussion of exactly what's happening at the molecular level here: What happened to my melted couverture?

The usual fix for seizing is to add more liquid, but I think you've got so much liquid in there that you can't agitate it well enough to break up the clumps. So you get lumps of seized chocolate swimming in liquid.

A better solution is to dissolve your chocolate in a small amount of boiling water, over medium temperature rather than in a double boiler. Since there is no milk in it at that point, you don't have to worry about overcooking the milk proteins. Then you can add the dairy to the hot chocolate syrup, then heat through. Because the chocolate is already dissolved, it will distribute evenly through the milk.

It shouldn't need any thickening agent. The chocolate is starchy enough on its own to thicken the dairy. (If you do like it with the starchy mouthfeel, you can add a small amount of cornstarch with the cold milk.)

The recipe I use runs something like this:

Put 1 ounce of bittersweet chocolate, 1 tbsp sugar, and a quarter cup of water in a small pot Cook over medium heat, stirring until it becomes a thickened syrup Add 8 ounces milk Heat through, stirring Add 1/2 tsp vanilla extract

I like to whip it with a stick blender. You can also use half-and-half for a richer result. You may want more sugar; you can add that at the table.

Similar recipes are also made in a double boiler, e.g. www.food.com/recipe/angelina-s-hot-chocolate-334398. I don't think the double boiler is necessary.

Note: it's better to use eating chocolate rather than unsweetened. Unsweetened chocolate isn't as thoroughly "conched", since it's usually used for cakes, where that doesn't matter as much. In a drink it'll be slightly gritty. (I'm also told that they use lower-quality beans, but I haven't done a taste test.)

  • 1
    Thanks! That definitely helped. I made a paste of 2 oz unsweetened chocolate + 2 tbsp water and then stirred in about 3/4 cup milk and a little sugar. It worked fairly well but there were still some clumps of chocolate paste in the pot, on my spoon and at the bottom of the serving cup. Is there any way to avoid this? Should I try using a whisk maybe? Thanks anyways
    – user52037
    Commented Nov 29, 2016 at 16:36
  • 1
    I've had the same problem. Hitting it with a stick blender helps; a whisk might also. Worst case you could strain it, but that's no fun. Commented Nov 29, 2016 at 17:01

I recommend making a 1:1 dark chocolate ganache (I prefer 70%) and storing it in the refrigerator. When you want cocoa, simply add 1-2Tbs of ganache to a mug, fill 1/2way with hot whole milk (never boil milk) and stir well (For a great cupola, use a stick-style milk frother to emulsify ). Top off with more hot milk.

1:1 ganache: 250g high quality dark chocolate in small pieces no bigger than a Lima bean 250g very hot heavy cream Place chocolate in a heat safe bowl with a capacity of no more than twice the volume of your chocolate Heat cream to scald but DO NOT BOIL Pour hot cream over chocolate and wait 3 minutes to let the chocolate begin to melt Starting in the center, slowly whisk in small circles, gradually expanding until homogeneous. You may think it’s not working, but it will, just keep in moving. In the end you’ll have a thick and glossy liquid which will firm up in the fridge.

The ganache will last several weeks in an airtight container in your fridge and has many uses.

  • What is the reasoning behind your 'never boil milk' aside? A cursory search didn't give me any reasons not to do so.
    – Onyz
    Commented Nov 2, 2023 at 14:25

No scientific answers, but great childhood memories. Keep it simple. My brother made our family of 9 hot chocolate it seemed, every Saturday morning.

He used 2 teaspoons of sugar & one teaspoon of coaco (per cup wanted) mixed well to remove the clumps then added just enough boiling water to make a smooth paste. He then gradually added about 1/2 cup water (per person) stirring using a wisk, over medium heat. Then continued to stir adding milk & heating until steaming & had a light colored skiff of small foamy bubbles on the top.

As an adult I still use this method but increase the coaco & use half & half in the amount I would use creamer in coffee. (I also use stevia as a sweetener.) The key is to make the paste & add water gradually & use a whisk to stir constantly. Try using whipping cream, unwhipped.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.