Bring a large pot of water to a boil over high heat.
Cook the penne according to package directions until al dente.
Before draining, reserve ¼ cup / 60 ml (2 fl oz) of the starchy cooking liquid.
Drain the pasta, do not rinse, and transfer it to a large serving bowl.
While the pasta cooks, combine the silken tofu, raw cashews, and hot water in a high-speed blender.
Blend until the mixture is completely smooth and creamy.
Add the drained sun-dried tomatoes, chopped garlic, basil, marjoram, salt, and pepper to the blender. Pulse until the are combined but small, flavorful chunks of tomato remain.
Pour the sauce over the hot pasta in the bowl.
Add the thawed artichoke hearts and toss everything together until well-coated. If the sauce seems too thick, add the reserved pasta water a tablespoon at a time until it reaches your desired consistency.
Serve immediately.
Don't skip reserving the pasta water! The starch in the water is a key emulsifier that helps the sauce cling beautifully to the penne and creates a silkier texture.
