Vegan cream sauce?

Crochetlove, here's the recipe

1/2 lb. wild mushrooms
3/4 lb. ripe tomatoes, peeled
1/4 lb. thinly sliced prosciutto
Salt to taste
2 tbsp. extra virgin olive oil
Freshly ground pepper to taste
1 tbsp. minced garlic
1 tsp. finely chopped jalapeno pepper
1 rosemary sprig or 1/2 tsp. dried
1/2 lb. angel hair pasta (capelli de'angelo) or vermicelli
1/2 c. cream
2 tbsp. butter
3/4 c. Parmesan cheese
1/2 c. shredded basil

Such as morels, chanterelles, ****ake or oyster mushrooms (or equal amount of cultivated mushrooms).

1. Rinse the mushrooms and pat them dry. Cut off and reserve the stems. Cut the mushroom caps into thin strips. There should be about 4 cups all together.

2. Cut away the cores of the tomatoes. Cut the tomatoes into 1/2 inch cubes.

3. Cut the prosciutto into very thin julienne strips.

4. In a kettle, bring 3 quarts of water to the boil for the pasta. Add salt to taste.

5. meanwhile, heat the oil in a casserole and add the mushrooms, salt and pepper. Cook, stirring, about 3 minutes and add the garlic, jalapeno and prosciutto, stir for 1 more minute. Add the rosemary.

6. Add the pasta to the boiling water and stir until the strands are submerged. Cook about 4 minutes, or to the desired degree to doneness scoop out and reserve 1/2 cup of the cooking liquid. Drain the pasta and return it to the kettle.

7. Add the tomatoes to the mushroom mixture and stir. Add the cream and bring to the boil. Add the pasta, the reserved pasta liquid, butter, 1/4 cup of the cheese and the basil and toss to blend. Serve in 4 heated pasta plates with the remaining cheese on the side.

I don't have a sub for the prosciutto, I was just going to leave it out. and for the parm I thought maybe a little nutritional yeast would work.