Place all the ingredients into a food processor: slivered almonds, lemon juice, water, almond milk, and salt.
Blend until almost smooth. You will have to stop the blender, scrape down the sides of the bowl and repeat until all ingredients are evenly combined. It can be difficult to blend or too thick, so you can add extra water, up to 5 tablespoons. You want to form a thick, fluffy mixture with almost no bites of almonds, just a grainy texture as regular ricotta. Blend between each addition and stop when it reaches a fluffy and creamy, slightly grainy texture. The whole process of blending, scraping the bowl takes about 2-4 minutes.
Taste and adjust by adding some of the recommended flavorings. Add more nutritional yeast to enhance the cheese flavor, more salt for savory cheese, and more lemon for tangy ricotta.