Preheat oven to 450 F. Line a baking sheet with foil. Wash broccoli crowns and cut into florets.
Melt the butter in the microwave. Add the cumin, chili powder, salt and sugar to the melted butter.
Pour butter mixture into a large bowl. Toss the broccoli florets in the butter mixture. Be sure that each piece of broccoli gets some of the butter mixture.
Place broccoli evenly spaced on a foil-lined baking sheet. Bake broccoli for 10-15 minutes, stirring half way through. Broccoli should be tender and lightly browned.