01 -
In a large skillet over medium heat, brown the Italian sausage with the diced onion until thoroughly cooked with no pink remaining. Break the sausage into small pieces as it cooks, then drain any excess fat from the pan.
02 -
Add the processed cheese and cream cheese to the skillet with the sausage and onion. Stir continuously over medium heat until both cheeses are completely melted and the mixture is smooth.
03 -
Whisk in the dry mustard powder, milk, and Worcestershire sauce into the cheese mixture. Continue cooking, stirring constantly, until the dip is hot and bubbly.
04 -
Stir in the sharp cheddar cheese until it's fully melted and the dip becomes creamy and well combined.
05 -
Serve the dip immediately while it's still warm with tortilla chips, crackers, or slices of crostini for dipping.