Quick Recipe Version (TL;DR)
Quick Ingredients
- 4 large bell peppers, halved lengthwise and seeded
- 2 tablespoons olive oil, divided
- 1 cup dry quinoa, rinsed
- 2 cups low-sodium vegetable broth (or water)
- 1 teaspoon kosher salt, divided (plus more to taste)
- 3 cloves garlic, minced
- 3 packed cups baby spinach, roughly chopped
- 1 1/2 cups cherry tomatoes, halved
- 1 teaspoon dried Italian seasoning
- 1/4 teaspoon black pepper
- 1 cup shredded mozzarella (about 4 ounces), divided
- 1/2 cup chopped fresh basil, divided
- 2 tablespoons balsamic glaze, plus more to serve
Do This
- 1) Heat oven to 400°F (204°C). Place pepper halves cut-side up in a baking dish; brush with 1 tablespoon oil and sprinkle with 1/4 teaspoon salt.
- 2) Bake peppers 10 minutes to soften slightly.
- 3) Simmer quinoa in broth with 1/2 teaspoon salt: bring to a boil, cover, reduce to low, cook 15 minutes; rest 5 minutes, then fluff.
- 4) Sauté garlic in 1 tablespoon oil for 30 seconds; add spinach and cook 1–2 minutes until wilted.
- 5) Mix quinoa with spinach/garlic, tomatoes, Italian seasoning, pepper, 3/4 cup mozzarella, and 1/3 cup basil. Taste and salt as needed.
- 6) Fill peppers, top with remaining 1/4 cup mozzarella, cover with foil, bake 15 minutes; uncover and bake 5 minutes until melty.
- 7) Rest 5 minutes, then drizzle with balsamic glaze and sprinkle with remaining basil.
Why You’ll Love This Recipe
- Classic caprese flavor, extra hearty: juicy tomatoes, basil, mozzarella, and balsamic—plus quinoa to make it filling.
- Weeknight-friendly: simple steps and hands-off oven time.
- Great for meal prep: leftovers reheat well for lunches.
- Easy to customize: add protein, swap greens, or change the cheese based on what you have.
Grocery List
- Produce: 4 large bell peppers, cherry tomatoes, baby spinach, fresh basil, garlic
- Dairy: mozzarella cheese
- Pantry: quinoa, olive oil, low-sodium vegetable broth (or water), dried Italian seasoning, kosher salt, black pepper, balsamic glaze
Full Ingredients
For the Peppers
- 4 large bell peppers (any color), halved lengthwise and seeded
- 1 tablespoon olive oil (for brushing)
- 1/4 teaspoon kosher salt (for seasoning peppers)
For the Quinoa Caprese Filling
- 1 cup dry quinoa, rinsed well and drained
- 2 cups low-sodium vegetable broth (or water)
- 1/2 teaspoon kosher salt (for cooking quinoa)
- 1 tablespoon olive oil (for sautéing)
- 3 cloves garlic, minced
- 3 packed cups baby spinach, roughly chopped
- 1 1/2 cups cherry tomatoes, halved
- 1 teaspoon dried Italian seasoning
- 1/4 teaspoon black pepper
- 1 cup shredded mozzarella (about 4 ounces), divided
- 1/2 cup chopped fresh basil, divided
To Finish
- 2 tablespoons balsamic glaze, plus more to serve
- Optional: extra torn basil leaves for garnish

Step-by-Step Instructions
Step 1: Heat the oven and prep the peppers
Arrange a rack in the center of the oven and preheat to 400°F (204°C).
Cut 4 large bell peppers in half lengthwise. Remove stems, seeds, and membranes. Place the pepper halves cut-side up in a 9×13-inch baking dish (or any baking dish that fits them snugly).
Brush the insides with 1 tablespoon olive oil and sprinkle with 1/4 teaspoon kosher salt.
Step 2: Par-bake the peppers
Bake the peppers for 10 minutes to give them a head start. This helps them turn tender without overcooking the filling later.
Keep the oven on. Set the baking dish aside while you make the filling.
Step 3: Cook the quinoa
While the peppers par-bake, cook the quinoa. In a medium saucepan, combine:
1 cup dry quinoa, 2 cups low-sodium vegetable broth (or water), and 1/2 teaspoon kosher salt.
Bring to a boil over medium-high heat, then reduce heat to low, cover, and simmer for 15 minutes.
Remove from heat and let stand (covered) for 5 minutes, then fluff with a fork.
Step 4: Sauté the garlic and wilt the spinach
Heat 1 tablespoon olive oil in a large skillet over medium heat. Add the minced garlic and cook for 30 seconds, stirring constantly, just until fragrant (avoid browning it).
Add 3 packed cups baby spinach. Cook for 1 to 2 minutes, stirring, until just wilted. Remove the skillet from the heat.
Step 5: Mix the caprese-style filling
In a large bowl, combine the cooked quinoa, the warm spinach-garlic mixture, 1 1/2 cups halved cherry tomatoes, 1 teaspoon Italian seasoning, and 1/4 teaspoon black pepper.
Stir in 3/4 cup shredded mozzarella and 1/3 cup chopped basil.
Taste and add more salt if needed (the amount can vary depending on how salty your broth and mozzarella are).
Step 6: Stuff the peppers and bake until melty
Spoon the quinoa mixture evenly into the par-baked pepper halves, packing it in lightly so each pepper is generously filled.
Sprinkle the remaining 1/4 cup mozzarella over the tops.
Cover the baking dish tightly with foil and bake at 400°F (204°C) for 15 minutes.
Remove the foil and bake for 5 minutes more, until the cheese is fully melted and the peppers are tender when pierced with a fork.
Step 7: Rest, garnish, and add balsamic drizzle
Let the peppers rest in the baking dish for 5 minutes (this helps the filling set up and makes serving easier).
Drizzle each pepper with about 1/2 tablespoon balsamic glaze (for a total of 2 tablespoons), then sprinkle with the remaining basil. Serve warm, with extra balsamic glaze at the table if you like that bold caprese finish.
Pro Tips
- Rinse quinoa well: This removes natural bitterness (saponins) and keeps the flavor clean and nutty.
- Don’t overcook the spinach: Just wilt it so it stays bright and doesn’t water down the filling.
- Use a snug baking dish: Peppers stay upright and hold their filling better when they’re packed closely together.
- Control moisture: If your tomatoes are extra juicy, stir them in at the end and avoid crushing them so the filling stays fluffy, not soggy.
- Add balsamic at the end: Glaze can burn or get bitter if baked; a fresh drizzle keeps it glossy and sweet-tangy.
Variations
- Add protein: Stir in 1 1/2 cups cooked chickpeas or 1 1/2 cups shredded rotisserie chicken with the quinoa mixture.
- Swap the cheese: Use 4 ounces fresh mozzarella pearls (halved) for bigger creamy pockets, or try fontina for extra melt.
- Make it spicy: Add 1/4 teaspoon crushed red pepper flakes to the garlic while sautéing.
Storage & Make-Ahead
Cool leftovers to room temperature, then store in an airtight container in the refrigerator for up to 4 days.
To reheat, place peppers in a covered baking dish and warm at 350°F (177°C) for 15–20 minutes, or microwave individual portions in 60–90 second bursts until hot.
Make-ahead option: prepare the quinoa filling up to 2 days in advance and refrigerate. When ready to cook, par-bake the peppers, fill, then bake as directed (you may need an extra 3–5 minutes if the filling is cold).
Nutrition (per serving)
Approximate per 1 stuffed pepper: 360 calories, 14 g protein, 45 g carbs, 14 g fat, 7 g fiber, 8 g sugar, 520 mg sodium.

