1. In a large skillet heat up the oil over medium heat. Add the sausage links and let them brown on each side continually turning to prevent from burning. (Cook for about 6-8 minutes). Remove the Sausage links onto a separate plate.
2. Add 1 tablespoon of the butter to the skillet and allow the butter to melt. Add in the sliced onion and garlic and sauté over medium heat for about 5 minutes making sure you’re mixing the onions so they don’t burn. When they have started to brown add in the other tablespoon of butter and mix in with the onions. Sprinkle the flour over the top and stir together.
3. Pour in a cup of the beef broth and mix into the onion mixture. It will be sludgy at this point. Add the rest of the beef broth and make sure the flour is mixed in with the broth using a fork or whisk. Let the sauce simmer over low heat for 5 minutes to thicken up.
4. Add the salt and pepper and the sausage links in with the gravy. Let the sauce continue to simmer for 3 more minutes to combine flavors.
5. Serve over mashed potatoes and with green peas.