Preheat oven to 375ºF. Heat oil over medium-high heat in pan and cook onion, carrots, and celery until soft, about 10 minutes. Stir in garlic, mushrooms, thyme, and sage. Let cook another 5 to 8 minutes, until liquid from mushrooms has evaporated. Gently pulse walnuts in a food processor. Add lentils, rice, breadcrumbs, tamari and vegetable broth. Pulse again until ingredients blend together, leaving visible bits and pieces. Empty mixture into the pan with cooked vegetables and cook for another 5 minutes. Taste and season with salt and pepper.
On a tray-sized piece of parchment paper, roll out one sheet of puff pastry until it’s about an inch wider on all sides. Empty contents of the pan lengthwise nearest to you, forming a loose loaf on the pastry sheet, leaving a 1/2-inch border all around. Carefully fold up ends, then fold over sides. Press seams together. Place on the prepared baking tray, seam side down. Brush with olive oil and sprinkle with salt. Bake for 25 minutes, or until the pastry turns golden brown. Remove from the oven and let sit for 5 minutes. Use a serrated knife to slice.
An “AMAZING” recipe!!!! EVERYONE who has tried it absolutely loved it!!!! It is always a favorite requested dish! Thank you so much for sharing. For those who find “meatless” Wellington a difficult concept, I simply call it Lentil Loaf!