Bring a large pot of water to a boil, salt it, add the pasta and cook until al dente. Drain, reserving a ladleful of pasta cooking water.
While the pasta is working, using a food processor, puree the parsley, parmigiano-reggiano, vegetable stock, almonds, tarragon, mint and garlic; season with salt and pepper. With the machine on, drizzle in the EVOO.
In a serving bowl, combine the artichoke hearts and pesto. Add the reserved pasta cooking water, then stir in the pasta and season with salt and pepper. In a bowl, season the tomatoes with salt.
Serve the pasta with the tomatoes and ricotta for mixing in.