For the clamshells:

First roast the potatoes: Preheat the oven to 425°F (220°C). Line a baking sheet with parchment paper. Put the sliced potatoes in a bowl with enough cold water to submerge them. Let them soak for a minute or so to rinse off the starch. Drain completely and dry with paper towels as best you can.

Drizzle the baking sheet with the olive oil and salt. Add the potatoes and toss to coat, then arrange in a single layer. Bake for 30 minutes, flipping once, until browned and crispy.

Start the sauce and pasta:

Bring 6 quarts (5.7 liters) salted water to a boil in a large pot. Boil the pasta until al dente according to package directions, then drain and set aside.

Preheat a large sauté pan over medium heat. Add 1 tablespoon of the oil and sear the mushrooms for about 5 minutes, sprinkling them with a little salt and tossing frequently. Remove from the heat and set aside.

Sauté the sliced garlic in the remaining 2 tablespoons oil for about 1 minute, until lightly browned. Add the onion and a pinch of salt and toss to coat. Cook until the onion is translucent, about 5 minutes.

Add the minced garlic and sauté for about 3 seconds more. Then add the nutritional yeast and toss to coat, lightly toasting it for about 1 minute to bring out the flavor.

Add the tomatoes to the pan and toss around, letting them break down a bit for about 2 minutes. Add the bay leaves, thyme, red pepper flakes, kelp powder, ½ teaspoon salt, and oregano. Stream in the wine and toss everything around with a wooden spatula to deglaze the pan. Raise the heat and add a generous amount of freshly ground black pepper as the wine reduces and the tomatoes break down further, about 3 minutes.

Lower the heat back to medium and add the vegetable broth and lentils to heat through. Add the lemon juice and parsley and mix well. Return the mushrooms to the pan along with the linguine and let cook for about 3 minutes.

Place on a serving platter family-style and stick the potatoes strategically into the pasta swirls so they resemble clam shells. Sprinkle with a little additional parsley and serve with lemon wedges and more red pepper flakes.