Step 1

In a small bowl, thoroughly mix sauce ingredients.

Step 2

Place lettuce in a large bowl.

Step 3

Bring a skillet sprayed with nonstick spray to medium-high heat. Add beef, onion, and seasonings. Cook and crumble for about 5 minutes, until beef is fully cooked and onions have softened.

Step 4

Remove skillet from heat. Add mustard, and stir until well mixed.

Step 5

Add beef mixture to the large bowl. Top with remaining ingredients.

Step 6

Top with sauce, or serve it on the side.