In a large pot, melt butter over medium heat. Add diced onions and cook until softened and translucent, about 5 minutes.
Add the ground beef and cook, breaking it apart with a spoon, until browned and cooked through, about 7-8 minutes.
Stir in minced garlic, crushed dried chili peppers, and ground cumin. Cook for another 1-2 minutes until fragrant.
Season the mixture with salt, black pepper, and sugar, stirring well to combine.
Add the canned diced tomatoes with their juices and the drained kidney beans. Stir to combine.
Bring the chili to a gentle simmer, then reduce heat to low and cook uncovered for 40-45 minutes, stirring occasionally, allowing flavors to meld and sauce to thicken.
Taste and adjust seasoning if needed before serving warm with your favorite toppings or cornbread.