This lentil casserole combines tender canned legumes with a bright tomato base and fresh rosemary. The mixture simmers on the stovetop to blend the flavors before getting a quick turn under the broiler to melt the cheese on top. It is a reliable meatless dinner for busy weeknights.
Using canned beans and lentils cuts the cooking time down to just over half an hour. You do not need to soak or boil any dried beans. The celery and onion build a savory foundation that makes the dish taste like it cooked all afternoon.
Why You’ll Love Lentil Casserole
- Sautéing the celery and onion first softens their texture and removes the sharp raw bite.
- Simmering the beans and tomatoes together on the stove thickens the juices so the final dish is not watery.
- Finishing the casserole under the broiler creates a browned, bubbling cheese crust in just a few minutes.
Lentil Casserole Ingredients
- Olive oil: Use regular or extra virgin olive oil to cook the vegetables.
- Lentils: Canned brown or green lentils work best. Rinse them well to remove the starchy canning liquid.
- Kidney beans: Light or dark red kidney beans hold their shape well during the simmer.
- Diced tomatoes: Keep the juice in the can. The liquid helps the vegetables and beans simmer without drying out.
- Rosemary: Fresh rosemary provides a strong herbal note. Strip the leaves from the woody stems before chopping.
- Cheddar cheese: Shred your own cheese from a block so it melts evenly under the broiler.
Exact quantities are in the recipe card below.
How to Make Lentil Casserole
Step 1: Sauté the aromatics
Warm the olive oil in a large oven-safe skillet or pot. Cook the diced onion and celery until they turn translucent and soft. This builds the flavor base for the casserole.
Step 2: Simmer the beans
Stir in the drained lentils, kidney beans, diced tomatoes, garlic, and rosemary. Season the mixture with salt and pepper. Bring it to a gentle boil, then lower the heat and let it simmer. This step reduces the tomato liquid and marries the flavors.
Step 3: Broil the cheese
Once the mixture is thick, make sure it is in an oven-safe dish. Sprinkle the shredded cheddar cheese in an even layer over the top. Place the dish under the broiler until the cheese is melted and slightly browned at the edges.
Storage Tips for Lentil Casserole
Store leftover casserole in an airtight container in the refrigerator for up to 4 days. Freeze in a sealed container for up to 3 months. Reheat portions in the microwave or on the stovetop over low heat until warmed through.
Expert Tips for Lentil Casserole
- If you do not have fresh rosemary, substitute two teaspoons of dried rosemary. Crush it between your fingers before adding it to the pot.
- You can use any melting cheese you have on hand. Monterey Jack or a vegan cheddar alternative will also work well.
- Make sure your skillet is oven-safe before placing it under the broiler. Avoid using pans with plastic or wooden handles.
What to Serve with Lentil Casserole?
Serve this hearty bean dish with a slice of crusty bread or garlic toast to soak up the tomato broth. A crisp green salad dressed in vinaigrette balances the heavy cheese topping.
Lentil Casserole Recipe FAQs
Can I use dried lentils instead of canned?
Yes, but you must cook them first. Boil half a cup of dried lentils in water until tender, then drain and add them to the skillet as directed.
Do I have to drain the canned tomatoes?
No. Pour the entire can of diced tomatoes into the pot. The juices provide the necessary liquid for the simmer.
Can I make this ahead of time?
You can simmer the lentil and tomato mixture up to two days in advance. When you are ready to eat, reheat the mixture on the stove, add the cheese, and broil.
Lentil Casserole
Ingredients
- 2 tablespoons olive oil 30 ml
- 1 medium yellow onion finely diced
- 1 celery stalk finely diced
- 1 clove garlic minced
- 1 can diced tomatoes undrained, 28 ounces / 794 g
- 1 can lentils rinsed and drained, 15 ounces / 425 g
- 1 can dark red kidney beans rinsed and drained, 15 ounces / 425 g
- 2 tablespoons chopped fresh rosemary 3 g
- 1/2 teaspoon kosher salt
- 1/4 teaspoon black pepper
- 1 1/2 cups shredded cheddar cheese 170 g
Instructions
- Heat the olive oil in a large oven-safe skillet or pot over medium heat.
- Add the diced onion and celery. Sauté for 3 minutes until the vegetables soften.
- Stir in the minced garlic, diced tomatoes with their juices, drained lentils, drained kidney beans, and fresh rosemary.
- Season the mixture with the kosher salt and black pepper.
- Bring the pot to a boil over medium-high heat.
- Reduce the heat to low. Simmer gently for 20 minutes, stirring occasionally, until the liquid reduces and thickens.
- Preheat your oven broiler to high. If your pot is not oven-safe, transfer the mixture to a small casserole dish now.
- Sprinkle the shredded cheddar cheese evenly over the lentil mixture.
- Broil for 2 to 4 minutes. Watch closely until the cheese melts and begins to brown.
