In a large, deep pot, evenly combine the sugar and 1 tablespoon of water to create a wet sugar mixture. Cook over medium heat, allowing the sugar to dissolve completely and begin to caramelize.

Stirring isn’t usually necessary at this stage, but if needed, gently swirl the pot or lightly stir to help the sugar melt evenly.

Continue cooking until the caramel reaches a deep amber color. If sugar crystals form along the sides of the pot, use a pastry brush dipped in water to gently wash them down to prevent crystallization.

Once the caramel reaches the correct color, turn off the heat. Carefully and slowly deglaze the caramel by ladling in the warm milk mixture in a thin, steady stream while whisking constantly with a long whisk. The caramel will bubble and expand vigorously, so stand back slightly and keep your hands protected.

When the bubbling and foam subside, add the remaining milk mixture more quickly. Once there is no longer active bubbling, pour in the rest of the milk mixture all at once and whisk until completely smooth.

Bring the mixture to a gentle simmer and maintain it, stirring constantly, for 5–10 minutes, or until slightly thickened and the raw cornstarch flavor has cooked out.

I like to switch to a spatula for stirring, then finish with a whisk at the end if I want to lightly foam the mixture for a more appealing finish.

Taste and adjust sweetness as needed. I typically add about 3 additional tablespoons of sugar, but adjust to your preference.

Once the flavor is balanced, stir in the vanilla. Serve warm in a mug and enjoy as is, or top with whipped cream, chocolate sauce, or a dusting of cocoa powder if desired.