Cook the sausage until browned, about 8 minutes. Be sure to break the sausage into small pieces as it cooks. Transfer the sausage to a paper towel-lined bowl to drain while you prepare the rest of the ingredients.
To a medium mixing bowl add the cream cheese, garlic, green onions, mustard, salt, pepper, and sausage. Use a wooden spoon or sturdy rubber spatula to mix everything together until evenly combined.
Spread 1/3 of the filling over one of the tortillas. I ignore the outer 2-inches on the left and right sides of the tortilla since those usually get discarded anyway.
Gently roll up the tortilla until it forms a long. Set aside, seam side down, and repeat with the two remaining tortillas.
Use a sharp knife to cut off both end of the tortilla log to where the filling starts. Cut the logs into 1/2-inch slices. Transfer to a serving platter.
Serve immediately or cover with plastic wrap and refrigerate until ready to serve (or up to 2 hours).
Notes
You can substitute 10-inch or 8-inch tortillas if needed. The amount of pinwheels will vary with the tortilla size change, but you should get a few more since you can fill more tortillas. They just won't be as big around.