01 -
Preheat your oven to 375°F (190°C). Lightly grease a baking dish large enough to hold the pepper halves snugly in a single layer. Spread marinara sauce evenly over the bottom of the dish if using.
02 -
Wash the peppers. Slice them in half lengthwise and remove seeds, ribs, and stems. Optionally trim the rounded bottom slightly so they sit flat without creating holes.
03 -
Place pepper halves cut-side down in the baking dish. Add ¼ inch of water if not using marinara sauce. Cover with foil and bake for 15-20 minutes. Remove from oven, drain water, and set aside. Keep oven preheated.
04 -
Heat olive oil in a skillet over medium heat. Add chopped onion and cook until softened and translucent, about 5-7 minutes. Add minced garlic and cook for 1 minute until fragrant.
05 -
Add thawed and squeezed spinach to the skillet. Stir well and cook for 2-3 minutes. Remove from heat.
06 -
Combine ricotta, beaten egg, ½ cup Parmesan, breadcrumbs (if using), Italian seasoning, salt, and pepper in a bowl. Mix thoroughly.
07 -
Stir the spinach, onion, and garlic mixture into the ricotta mixture. Adjust seasoning to taste.
08 -
Arrange pepper halves cut-side up in the baking dish. Spoon ricotta filling generously into each half, mounding it slightly.
09 -
Sprinkle extra Parmesan on top of the stuffed peppers. Bake uncovered in the oven for 30-40 minutes, or until peppers are tender and tops golden brown. Tent with foil if browning too quickly.
10 -
Remove peppers from the oven and let rest for 5-10 minutes before serving. Garnish with fresh parsley or basil, if desired.