Start by bringing a large pot of salted water to a boil and drop in the tagliatelle. Cook until al dente, as per the package instructions. Drain the pasta and drizzle with a touch of olive oil to keep it from sticking. Sprinkle with a pinch of salt and pepper for a bit of flavor.

Melt the plant-based butter in a medium pot over medium heat. Once melted, whisk in the flour to form a paste. Cook this roux for about 1 minute to eliminate the raw flour taste. Gradually add the oat milk while whisking constantly to create a silky base for your sauce.

Turn the heat to medium-high and bring the sauce to a light boil. Stir in the sherry, tomato paste, Old Bay seasoning, and a touch of salt and pepper. Allow the mixture to simmer gently for about 5 minutes so the flavors can meld together beautifully and the sauce thickens.

Carefully add the lump crab meat to the sauce, taking care not to break it apart too much. Simmer for another 2-3 minutes to warm the crab and infuse it with the luxurious flavors of the sauce. Adjust the seasoning if needed, ensuring each bite will be perfectly balanced.

Spoon the creamy sauce generously over the freshly cooked tagliatelle and toss lightly to coat the pasta. Plate the dish neatly in deep pasta bowls. Add a sprinkle of bright parsley, a dash of smoky paprika, and a fresh lemon wedge on the side to elevate the presentation and flavor.