Step 1: Cook the Lentils

In a medium saucepan, combine the rinsed lentils with 3 cups of vegetable broth or water. Bring to a boil, then reduce the heat to a simmer. Cook for 25-30 minutes, or until the lentils are tender but not mushy. Drain any excess liquid very well and set aside.

Step 2: Prepare the Oven and Pan

Preheat your oven to 375°F (190°C). Lightly grease a 9×5 inch loaf pan and line it with a strip of parchment paper, leaving some overhang on the long sides. This “sling” will make it much easier to lift the loaf out of the pan after baking.

Step 3: Sauté the Vegetables (Building the Flavor Base)

While the lentils are cooking, heat the 2 tablespoons of olive oil in a large skillet or Dutch oven over medium heat. Add the finely chopped onion, carrots, and celery (the “mirepoix”). Cook, stirring occasionally, for 8-10 minutes, until the vegetables have softened and the onions are translucent.

Add the finely chopped mushrooms and continue to cook for another 10-12 minutes. The mushrooms will first release a lot of water. Keep cooking until that water has completely evaporated and the mushrooms begin to brown and caramelize. This step is crucial for developing deep, savory flavor. Finally, add the minced garlic and cook for one more minute until fragrant.

Step 4: Combine the Loaf Mixture

In a large mixing bowl, combine the sautéed vegetable mixture with the cooked and drained lentils. Add the toasted walnuts, rolled oats, breadcrumbs, tomato paste, soy sauce (or tamari), fresh thyme, fresh rosemary, smoked paprika, salt, and pepper.

Using a potato masher or the back of a large fork, mash the mixture together. You are not trying to create a smooth paste. Aim to mash about half of the lentils, leaving the other half whole. This creates a binder while maintaining a wonderful texture. Stir everything together until it’s very well combined.

Step 5: Form and Bake the Loaf

Transfer the lentil mixture to your prepared loaf pan. Use a spatula or your hands to press it down firmly and evenly into the pan. This is important for helping the loaf hold its shape. Bake for 40 minutes.

Step 6: Prepare and Apply the Glaze

While the loaf is in its initial baking phase, prepare the glaze. In a small bowl, whisk together the balsamic vinegar, ketchup, maple syrup (or brown sugar), and soy sauce (or tamari) until smooth.

After the loaf has baked for 40 minutes, carefully remove it from the oven. Evenly spread half of the glaze over the top of the loaf. Return the loaf to the oven and bake for another 15-20 minutes, or until the loaf is firm to the touch and the glaze is bubbly and caramelized.

Step 7: The Crucial Resting Period

This is the most important step for a sliceable loaf! Once baked, remove the loaf from the oven and let it cool in the pan on a wire rack for at least 15-20 minutes. Do not try to slice it while it’s piping hot, or it will be crumbly. This resting time allows the loaf to set up and firm. Use the parchment paper sling to lift the loaf out of the pan. Serve warm with the remaining glaze for spooning over individual slices.