Preheat the oven to 375 degrees F.
In a large saucepan, combine the tomatoes and their juices, tomato paste, garlic powder, salt, pepper, oregano, onions and black beans. Bring to a boil over medium-high heat, and then reduce the heat and simmer, uncovered, for about 30 minutes.
Meanwhile, bring a large pot of salted water to a boil. Add the lasagna noodles and cook to al dente according to package directions. Drain the noodles well.
Spread 1 cup of the prepared sauce in a 9- by 13- by 2-inch baking pan. Make three layers each of noodles, sauce and Tofu Ricotta. End with the sauce and make sure the noodles are completely covered or they will dry out during baking. Bake for 45 minutes, uncovered. Allow the dish to stand for 15 minutes before cutting into squares and serving.
Add the cashews to a food processor and grind them. Then crumble in the tofu, and add the yeast, olive oil and basil. Season with salt and pepper. Store in an airtight container in the fridge until ready to use. Keeps well for at least a week.
To press tofu, drain any liquid from the block of tofu. Fold paper towels around the tofu and then set a big wrought iron skillet on top of it to press out the excess moisture. Allow to sit for about an hour to press.