Oat and Vegetable Baked Casserole
A hearty, wholesome casserole with seasonal vegetables and oats, baked until golden and creamy. This american-inspired one pot (vegetarian) ready in about 55 minutes pairs medium carrots, medium zucchini, small onion for a weeknight-friendly dinner that comes together with one pan and minimal cleanup. Each serving lands at about 300 calories and feeds 4, so it slots cleanly into a weekly meal plan and pairs well with a quick salad or grain on the side. Tap "Plan a meal with the AI" below to drop this recipe into your week and send the ingredients straight to Instacart. Nutrition values are approximate, calculated from USDA FoodData Central (fdc.nal.usda.gov) — verify against ingredient labels for any health-driven dietary plan.
Ingredients
- 2 medium carrots
- 1 medium zucchini
- 1 small onion
- 1 cup oats
- 1/2 cup milk
- 1/2 cup cheddar cheese
- 2 cloves garlic
- 1 tbsp olive oil
- 1/2 tsp salt
- 1/4 tsp black pepper
Instructions
- Step 1: Preheat oven to 375°F. Peel and dice 2 medium carrots and 1 medium zucchini into 1/2-inch cubes. Finely chop 1 small onion.
- Step 2: Heat 1 tbsp olive oil in a skillet over medium heat. Add the diced carrots, zucchini, and onion, and cook for 5 minutes until slightly softened. Add 2 minced garlic cloves and cook for 1 minute until fragrant.
- Step 3: In a bowl, combine the cooked vegetables, 1 cup rolled oats, 1/2 cup milk, 1/2 cup shredded cheddar cheese, 1/2 tsp salt, and 1/4 tsp black pepper. Transfer to a greased 8x8-inch baking dish.
- Step 4: Bake for 30-35 minutes until the top is golden and the edges are bubbling.
Frequently asked questions
How long does Oat and Vegetable Baked Casserole take to make?
Total time is about 55 minutes (20 min prep + 35 min cook). Most home cooks find this fits comfortably into a weeknight; double the batch on Sunday for two dinners.
How do I store leftover Oat and Vegetable Baked Casserole?
Cool to room temperature within 2 hours, then store in an airtight container in the fridge for up to 4 days. Reheat covered in a 350°F oven for 10-12 minutes, or microwave at 70% power in 60-second bursts to keep medium carrots from drying out.
Can I substitute ingredients in Oat and Vegetable Baked Casserole?
Yes — most ingredients in this recipe have flexible swaps. For oil, use any neutral high-smoke-point oil (avocado, grapeseed, refined coconut). For aromatics, dried herbs at ⅓ the volume of fresh work in a pinch. The full ingredient list is shoppable on Instacart so you can see substitutes in real time.
How do I scale Oat and Vegetable Baked Casserole for a different number of people?
The recipe is written for 4 servings. Multiply each ingredient by (your serving target / 4). Cook time stays roughly the same up to 2x; for 3-4x batches, switch from a skillet to a sheet pan or stockpot so the food isn't crowded — overcrowding steams instead of browns.
Is Oat and Vegetable Baked Casserole vegetarian?
Yes — this recipe is tagged vegetarian based on its ingredient list. Always cross-check labels for packaged ingredients (sauces, broths, condiments) since formulations vary by brand.
What others are saying
- ★★★★★
Perfect for a quick weeknight dinner. The oats gave it a nice texture.
- ★★★★★
This casserole was a hit with my kids! Easy to make and packed with veggies.
- ★★★★☆
Good flavor, but it took longer to bake than the recipe said.
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