Heat oil in a skillet over medium heat
Add onion and cook until softened
Add ground beef, paprika, garlic powder, salt, and pepper
Cook until browned, 7–10 minutes, then drain grease
Stir in ½ c BBQ sauce and Worcestershire, simmer for 2 minutes then remove from heat
Preheat oven to 350°F (175°C) and spray a baking dish with nonstick spray
Slice brioche buns in half and place bottoms in the baking dish
Spoon beef mixture onto buns
Top with cheese, bacon, a drizzle of remaining BBQ sauce, crispy onions, and jalapeño
Add top buns
Mix melted butter, garlic, parsley, red pepper flakes, onion powder, and lemon juice
Brush tops of buns with cowboy butter
Bake for 12–15 minutes or until cheese melts and buns are golden
Serve warm