Prepare biscuits according to package directions - preheat oven to bake biscuits but let dough sit, covered (on counter or in refridgerator) while you prepare the gravy. Remember the secret to great biscuits is to use COLD margarine or shortening and to not overmix.
Turn stove on to medium high, and preheat a drizzle of vegetable oil in the pan. When pan is hot, add chopped onions and saute until almost cooked. Add frozen sausage crumbles and continue to saute until cooked. Set aside cooked onion/sausage mixture in a bowl.
In the same pan, reduce heat to medium, and prepare a roux by mixing about 2-3 tablespoons flour with enough vegetable oil to make a heavy paste (about 1-2 tablespoons of oil). Add oil and/or flour to get the correct consistency. Stir and cook the roux for a couple of minutes over the medium heat, then slowly add about a cup of soymilk to the mixture, stirring continuously. You must stir continously to avoid lumps.
Contiune to simmer the gravy over medium heat and add more soy milk as needed (this may require several cups of milk). If you accidentally add too much milk, just add a bit more flour (not more than a teaspoon at a time). Also, the longer you cook the gravy, the more it will reduce and thicken.
As the gravy is simmering and reducing, put the biscuits in the oven and bake according to package instructions.
Add the onion/sausage mixture to the gravy and continue to stir and simmer until the biscuits are done. Add salt and pepper to taste - you will probably find that you'll use more salt and pepper than you expected.
Halve the warm biscuits and pour gravy mixture over them and serve. Yum!