Mix ground beef with garlic powder, onion powder, smoked paprika, Worcestershire sauce, salt, and pepper until just combined.
Divide into 8 portions and flatten into thin patties.
Combine shredded cheddar, cream cheese, and bacon bits for the filling, then spoon a tablespoon into the center of 4 patties.
Top each with another patty, pressing edges to seal. Brush seams with beaten egg to keep the filling inside.
Sear patties in a skillet over medium-high heat for 3–4 minutes per side until browned.
Bake at 375°F (190°C) for 10–12 minutes until hot inside and the cheese is melted.
Toast brioche buns until golden.
Assemble burgers with your favorite toppings and serve while the centers are still molten.