Yes, chocolate, especially dark chocolate, can be used to balance the heat in chili-based dishes. It adds a subtle sweetness and richness that complements the spicy flavors.
Chocolate contains compounds that interact with the taste receptors on your tongue, helping to mellow out the spiciness of chili peppers. Specifically, the fat content in chocolate coats the receptors, reducing the burning sensation caused by capsaicin (the compound that makes chili peppers hot). The subtle bitterness of dark chocolate also provides a counterpoint to the sweetness and savory elements in the dish, creating a more complex and balanced flavor profile. When adding chocolate to chili, start with a small amount (about a square or two of dark chocolate per pot) and taste as you go. Stir it in towards the end of the cooking process, allowing it to melt completely and incorporate evenly into the sauce. The chocolate will add depth and complexity, enhancing the overall taste of the chili.
Use unsweetened or dark chocolate with a high cocoa percentage (70% or higher) to avoid making the chili too sweet. Milk chocolate contains too much sugar and can throw off the balance of flavors.