Heat a skillet to medium-high. Add ground beef and cook 5–7 minutes, breaking into crumbles until golden brown. Drain excess fat and set aside.

Return skillet to medium heat. Add chopped onions and cook 3–4 minutes until translucent. Stir in minced garlic and chili powder, cooking 30 seconds until fragrant.

Stir in tomato sauce, ketchup, Worcestershire sauce, brown sugar, and mustard. Season with a pinch each of salt and pepper. Mix well to blend flavors.

Lower heat to medium-low and simmer mixture 5–7 minutes, stirring occasionally until sauce thickens and coats beef.

If desired, brush slider buns with melted butter and toast in a dry skillet or oven at 350°F for 3–5 minutes until golden and crisp.

Spoon the sloppy joe mixture generously onto toasted buns. Top with cheddar cheese, pickles, or jalapeños if you like. Serve hot.