01 -
Spread a generous layer of sun-dried tomato pesto evenly on one side of each bread slice.
02 -
Place a slice of mozzarella cheese on the pesto-covered side of one bread slice, then top with the second slice, pesto side down.
03 -
Heat a skillet over medium heat and melt 1 tablespoon of unsalted butter until sizzling.
04 -
Place the sandwich in the skillet, cooking for 3-4 minutes until golden brown. Flip and grill the opposite side until golden and the cheese melts, approximately 3-4 more minutes.