Melt butter in a small saucepan over medium-low heat, then add minced garlic immediately—you want it to bloom gently for about 60 seconds. The kitchen will smell noticeably different the moment garlic hits warm butter, which is your sign the temperature is right. I always add the parsley, lemon zest, salt, pepper, and smoked paprika directly into the warm butter off heat because high temperatures burn the herbs. Stir everything together and let it cool for 2 minutes.

Brush both sides of each bread slice with the garlic butter mixture using a pastry brush or the back of a spoon. Don't skip the edges—those become the crispiest, best part. I learned this mistake the hard way when I only buttered the flat sides and wasted perfectly good edges. Make sure the butter coats evenly because dry spots will taste like plain toasted bread.

Combine the shredded mozzarella and grated parmesan in a small bowl, then sprinkle the mixture generously over the buttered side of each slice. Press the cheese gently so it adheres to the butter instead of sliding off mid-grill. This is where the summer BBQ side disappears from the table because cheese always wins. Don't be stingy here—the cheese is what makes people reach for seconds.

Heat your grill to medium-high heat (around 400°F), then oil the grates lightly with the remaining tablespoon of olive oil. Test the temperature by holding your hand 6 inches above the grates—you should feel serious heat, but not an aggressive flame. I always use tongs to run an oiled paper towel across the grates because it prevents sticking without making the bread soggy.

Place each bread slice cheese-side up on the grill grates and close the lid for exactly 3 to 4 minutes. Don't walk away and definitely don't flip. The bottom develops that signature crunch while the cheese melts above. You'll hear gentle sizzling—that's the sound of butter rendering into bread, which is the whole point. When the bottom releases easily from the grates, it's done.

Carefully flip each slice and grill the other side for 1 to 2 minutes until the bottom has char marks and feels firm to the touch. The already-buttered side faces down now, and it doesn't need cheese because one side gets all the toppings. This is where impatience costs you—flip too early and the cheese doesn't stay put, flip too late and the first side burns. I use a thin spatula and move quickly.

Transfer each slice to a serving platter, and taste-test one immediately because this is your moment to adjust seasoning if needed. Sometimes the grilling intensifies salt, sometimes the garlic demands a touch more. Either way, you'll have your answer while the bread still holds warmth.