This rich homemade hot chocolate is the ultimate snow-day treat

In the kitchen - at home or our lovely Washington Post Food Lab - the most common types of happy accident are not what you'd expect. They might involve a piece of food falling right into my dogs' waiting mouths or that time when I was testing a recipe that I knocked my glass mug off the counter and rather than shattering on the floor, it got stuck between two stools (true story). Those unplanned culinary genius moments? Few and far between.

That is, until now.

While on the hunt for a decadent, thick, full-flavored hot chocolate, I plucked two recipes to test from our massive collection of cookbooks. One was from Alice Medrich's "Chocolate Holidays," the other from Lisa Yockelson's "ChocolateChocolate." Because they're pretty quick and easy to test and because I had an array of willing tasters in the Lab, I decided to make them back to back. They were both good, and we liked different things about each recipe. With a little bit of both batches left, more intending to just clean up than invent anything, I said, "I wonder what would happen if I combined these" and then unceremoniously dumped them into one bowl.

We laughed about how the world might end. I cracked a line about disrupting the space-time continuum.

After finishing the dishes, I decided to go in for one last taste, because why not (or because my willpower is slim when it comes to chocolate). Well, guys, it was darn good, if not world-ending. I called in the rest of the team to try this Frankenstein hot chocolate, and the verdict was unanimous. The hybrid was the winner. While one recipe had been a bit thin on texture but great on flavor and the other was thick but not quite sweet enough, together they were beautiful.

After that it was a simple matter of combining the ingredients and tweaking the amounts for scale and measurements that didn't involve odd fractions.

The trifecta of chocolate - powder, bittersweet, semisweet - helps strike a happy balance in this rich brew with fruity notes. It is thick but not sludgy and sweet without being cloying. Try it cold for an almost-milkshake experience (I speak from experience, several times over).

Depending on your taste, you can experiment with the proportions of the bittersweet and semisweet chocolates. Another way to add a personal flourish for this cup: Top it with marshmallows and dollops of whipped cream.

You might as well go all out and make the effort. I'm no longer leaving my best hot chocolate up to chance, and neither should you. Leftovers reheat well in the microwave or on the stove top.

Triple Hot Chocolate

1 cup water

1 tablespoon Dutch-processed cocoa powder (see note)

3 1/2 ounces semisweet chocolate (55 to 60 percent cacao), chopped

2 1/2 ounces bittersweet chocolate (about 70 percent cacao), chopped

1 1/4 teaspoons sugar

1 3/4 cups milk (whole, low-fat or nonfat)

Pinch salt

1/4 cup heavy cream

1/4 teaspoon vanilla extract

Bring the water just to a boil in a medium saucepan over high heat.

Remove from the heat and add the cocoa powder, stirring until smooth. Add the semisweet and bittersweet chocolates, sugar, milk and salt, stirring until most of the solid chocolates have melted. Return the saucepan to the stove top over low heat, stirring until the chocolates have completely melted.

Add the heavy cream; increase the heat to medium and whisk rapidly and constantly until the mixture is well incorporated, smooth and heated through, with small bubbles at the edges of the pan and steam wafting off the top. Do not allow it to boil or bubble rapidly. If you are monitoring the temperature with an instant-read thermometer, aim for 150 to 160 degrees.

Remove from the heat and whisk in the vanilla extract. Serve right away.

Serves a generous 6 (makes 3 1/4 cups)

Note: I prefer Dutch-processed cocoa powder here, because it has been treated to reduce acidity, meaning you get richer chocolate flavor.

Nutrition Calories: 220; Total Fat: 15 g; Saturated Fat: 9 g; Cholesterol: 25 mg; Sodium: 85 mg; Carbohydrates: 22 g; Dietary Fiber: 2 g; Sugars: 17 g; Protein: 4 g.

Adapted from "Chocolate Holidays: Unforgettable Desserts for Every Season" by Alice Medrich (Artisan, 2005) and "ChocolateChocolate" by Lisa Yockelson (Houghton Mifflin Harcourt, 2005).