A hearty and nutritious vegetarian bake featuring red lentils, mushrooms, onions, and cheese, bound together with eggs for a golden, savory finish. Perfect for weeknight dinners or meal prep, this dish is rich in plant-based protein and fiber while staying light and satisfying. Serve with salad, green veggies, or baked potatoes for a complete meal.
1 ovenproof baking dish (approx. 25 × 16 × 6 cm, or similar size)
1 medium saucepan
1 medium frying pan
1 Sieve
1 mixing spoon or spatula
1 Knife and chopping board
1 Grater (for cheese)
1 measuring jug (for stock)
Ingredients
180gsplit red lentils
350mllow-salt vegetable stockor water
1tspolive oil
20gbutterplus extra for greasing
1large onionroughly chopped
200gmushroomssliced
2clovesgarlicfinely chopped
1tspdried sageoptional
1tspyeast extractoptional
120ggrated cheesecheddar or similar
1tbspfresh parsleychopped
2medium eggslightly beaten
Salt and pepperto taste
Instructions
Prepare the Oven and Dish: Begin by preheating your oven to 200°C (180°C Fan) / Gas Mark 6. While the oven heats, take a medium-sized ovenproof dish (around 25 × 16 × 6 cm) and lightly grease the inside with butter. This will prevent the bake from sticking and make serving much easier. If you prefer a thinner bake with a slightly shorter cooking time, use a larger but shallower dish.
Rinse and Cook the Lentils: Place the red lentils into a sieve and rinse them thoroughly under cold running water until the water runs clear. This removes excess starch and helps prevent them from turning too sticky.Transfer the rinsed lentils into a medium saucepan and pour in the vegetable stock or water. Bring the liquid to a gentle boil over medium heat. Once boiling, reduce the heat to low and let the lentils simmer slowly, uncovered, for about 20–30 minutes, or until all the liquid has been absorbed and the lentils are soft but not mushy. Stir occasionally to avoid sticking. When ready, remove the saucepan from the heat and set aside to cool slightly.
Cook the Aromatic Base: While the lentils are simmering, heat the olive oil and butter together in a medium frying pan over low to medium heat. Add the chopped onion along with a small pinch of salt and pepper. Cook gently, stirring often, until the onion softens, turns golden, and begins to caramelize slightly—this will take around 10–15 minutes. Slow cooking is important here, as it develops sweetness and depth of flavor.
Add Mushrooms and Seasonings: Once the onions are tender and lightly browned, add the sliced mushrooms to the frying pan. Stir well and allow them to cook down for about 8–10 minutes until they release their moisture and turn a deep golden brown. Next, add the finely chopped garlic, the dried sage (if using), and a little extra salt and pepper. Stir everything together and cook for another minute until fragrant. When done, remove the pan from the heat.
Combine Lentils with Vegetables: Pour the cooked onion, mushroom, and garlic mixture into the saucepan of lentils. Stir well to ensure the flavors are evenly distributed. At this stage, add the yeast extract if you are using it—it gives a subtle savory depth. Next, mix in the grated cheese and chopped parsley, folding gently until everything is well incorporated and the cheese begins to melt slightly.
Add the Binding Eggs: Allow the lentil mixture to cool just a little before stirring in the lightly beaten eggs—this prevents the eggs from scrambling. Mix thoroughly so the eggs bind all the ingredients together, creating a creamy but firm texture that will set perfectly once baked.
Assemble the Bake: Carefully transfer the prepared mixture into your buttered baking dish, spreading it evenly with the back of a spoon or spatula. Smooth out the surface so it bakes consistently and rises evenly in the oven.
Bake Until Golden and Set: Place the dish on the middle shelf of the oven and bake for around 35 minutes. Cooking time may vary depending on your dish size: a shallower dish will cook more quickly, while a deeper one may take slightly longer. You’ll know it’s ready when the top is golden, the bake has risen slightly, and a skewer or cocktail stick inserted into the center comes out clean with no wet mixture clinging to it.
Rest and Serve: Once fully baked, remove the dish from the oven and allow it to rest for 5 minutes before cutting. This resting period makes it easier to slice into neat portions without crumbling. Divide into four generous servings and enjoy hot.
Serving Suggestions: Serve this bake with a crisp green salad, lightly steamed seasonal vegetables, or comforting sides such as baked or roasted potatoes. Its rich, savory flavor pairs beautifully with fresh greens or tangy dressings, balancing the richness of the cheese.
Storing and Reheating Leftovers: If you have leftovers, let the bake cool completely, then store covered in the refrigerator for 2–3 days, or freeze for up to 1 month. When reheating, cover with foil and warm gently in a medium oven until piping hot, or heat individual portions in the microwave for convenience.
Notes
Red lentils cook quickly and don’t require soaking, making them an excellent base for a speedy bake.
Caramelizing the onions slowly develops a natural sweetness that balances the earthy lentils.
Mushrooms add a meaty depth of flavor, making this dish satisfying even for non-vegetarians.
Cheese and eggs act as the binding agents, giving structure and a rich, savory taste.
The bake can be made in advance, refrigerated, and reheated without losing its texture.