Add the bread flour, vegan buttermilk, sour cream, and salt. Stir everything together with your hands or a wooden spoon until all the flour is wet. It will be a VERY sticky dough.
Remove the dough and place it onto a lightly floured surface. Knead the dough extensively, using a dough scraper as necessary to keep it from sticking. Avoid dusting with additional flour.
After about 15-20 minutes of constant kneading, your dough will begin to form into a messy ball that isn't nearly as sticky as when you started. Place the dough ball into a lightly greased bowl. Cover it with a lid and allow the dough to rise (or "proof") until it has doubled in size (approximately 1 hour).
Punch the dough to release the gasses. Knead the dough for about a minute to shape it into a ball again. Divide the dough into 8 equal pieces--use a scale to be precise.
Roll each piece into a ball about the size of a tennis ball. Press each ball onto a plate of semolina flour. Flip it over and repeat, so that each side (the top and the bottom--NOT the sides) is lightly covered with semolina flour.
Allow the balls to proof for at least one more hour. They will not have doubled in size, but they will be a bit larger. At this point, preheat the oven to 450° F.
On a large non-stick or cast iron pan, add a little vegetable oil over low heat. Take each piece of dough and once more, lightly dust the top and bottom with additional semolina flour before placing them on the hot pan, pressing the tops gently. Cook each side for approximately 5 minutes, making sure to keep the heat low enough that they don't burn.
Place the English muffins in the oven for another 25 minutes, until they are fully cooked inside.