Warm the olive oil in a saute pan over medium heat. Add the onions and cook until they soften, for about 5 minutes. Then, stir in the garlic and cook for 1 minute.
Add the sausage pieces and cook until they change color. Transfer them to a plate and set it aside.
Lower the heat and add butter to the same pan. Warm until the butter melts. Then, stir in the flour. Whisk continually to form a blonde roux (light to medium brown) for 10-15 minutes.
Pour the beef broth over the roux and whisk to combine - careful to scrape up any bits stuck to the bottom of the pan.
Increase the heat and bring the mixture to a boil. Stir in the mustard, tomato paste, salt, pepper, allspice, and nutmeg. Reduce the heat and simmer for 10 minutes or until the sauce thickens.
Return the sausage to the pan and stir to combine.
Notes
Expert Tips
It's easy to overdo the salt with this dish. The first couple of times I made it, I didn't think about the salt in the butter and broth and slightly overdid it. I recommend using low-sodium beef broth and unsalted butter to control how much salt you include.
Nutrition Disclosure:
The nutritional information shown is an estimate provided by an online nutrition calculator. It should not be considered a substitute for professional advice.