On a clean counter or cutting board, mix together the all-purpose flour and semolina flour. Make a well in the center and add the egg, beetroot puree and salt. Begin kneading and mixing the dough until it all comes together. This will take quite a bit of time and effort so you can alternatively use a stand mixer with a dough hook to bring the dough together if you have one and then knead for a few minutes by hand. Once the dough comes together, wrap in plastic wrap and allow to sit for about 20 minutes. Meanwhile, make the ravioli filling.
2 c all-purpose flour, 1 c semolina flour, 1 egg, ¾ c beetroot puree, ¼ teaspoon salt