01 -
Place a skillet over medium heat and allow it to come to temperature.
02 -
Brush one side of each bread slice evenly with olive oil or softened butter.
03 -
On the uncoated side of two bread slices, layer fresh spinach leaves, crumbled feta, mozzarella, chopped sun-dried tomatoes, sliced Kalamata olives, and a sprinkling of dried oregano.
04 -
Top each assembled slice with a second piece of bread, keeping the oiled or buttered side facing outward.
05 -
Transfer sandwiches to the hot skillet and cook for 3–4 minutes on each side, pressing gently with a spatula, until the bread is golden and the cheese is melted.
06 -
Remove from skillet, slice each sandwich in half, and serve immediately while warm.