Popeye Pizza

INGREDIENTS

• 1 cup all-purpose flour, plus more for work surface
• Fine sea salt
• 1/4 teaspoon active dry yeast
• 2/3 ounce Gruyere cheese, grated
• 1 ounce young pecorino cheese, broken into 4 to 5 pieces
• 1 1/8 ounces buffalo mozzarella cheese, broken into 4 to 5 pieces
• 2 pinches freshly ground black pepper
• 3 or 4 thin slices garlic
• 1/4 pound fresh spinach, stems removed
• 1 to 1 1/2 tablespoons extra-virgin olive oil, for serving