Mix softened butter with garlic powder, celery salt, and onion powder 30 minutes ahead so flavors meld together, creating a more cohesive and robust garlic butter that won't taste powdery.

Choose a day-old sourdough loaf rather than fresh bread—it has a sturdier crumb structure that won't collapse when stuffed and will crisp up beautifully without becoming dry.

Shred Monterey Jack cheese into thin pieces and distribute it evenly throughout the bread channels rather than using chunks, ensuring every bite has melted cheese and faster, more uniform melting.

Spread Dijon mustard thinly on the bread's interior surfaces before adding cheese—its acidity cuts through richness and prevents the filling from tasting one-dimensional or overly heavy.

Add fresh lemon zest (not just juice) to the butter mixture and sprinkle a tiny amount on top after baking for a bright, aromatic finish that elevates the dish from good to restaurant-quality.