First things first: Make sure you thaw the puff pastry or phyllo dough in the fridge the night before!
Preheat the oven to 400℉ (205℃) now if you're not prepping the filling in advance. And line a rimmed baking sheet with a piece of parchment paper.
Are your lentils cooked? If not, do that now, before you start chopping anything.
In a large skillet, warm the olive oil over medium heat. Cook the onion and carrot until softened, about 10 minutes…don’t rush this! It makes a difference. Once cooked, place in a large mixing bowl along with the cooked lentils.
In the same skillet, cook the mushrooms over medium heat until they release their water and look browned, 8-10 minutes. Then, add the garlic and cook, stirring constantly, 1 minute.
To the mushrooms, add the nutritional yeast, garlic powder, onion powder, thyme, cumin, bouillon concentrate, balsamic vinegar, and water. Cook until the liquid mostly evaporated, about 2-3 minutes. This is important, so your wellington is not soggy!
Add mushroom mixture to the bowl with the lentils, mix thoroughly. Add the panko crumbs, mix again and taste. Need more salt and pepper? Season well until it really pops.
Roll out your first puff pastry sheet on a well floured surface, so it’s about 10 x 15 inches in size. If you're using a puff pastry block like Tenderflake, press the two halves together to close the seam, then place the block seam side down and roll.
Place half of the lentil mixture in the centre of the sheet, leaving a 3 inch border. You’ll want to really press it firmly with your hands to help pack it down.
Fold the short sides over the filling first. Then, fold the long sides over the filling, it’s okay to stretch them a bit to make sure they overlap well. Carefully flip over and place on a parchment lined baking sheet and repeat with the second sheet and filling.
Bake for 25-35 minutes, until the pastry is golden brown and crisp. Let cool for 5 minutes and then slice each wellington into 4-6 slices.
This vegan wellington is delicious served warm or at room temperature…so if you need the oven for another side dish, just bake the wellington first!