1. Mix ground beef, minced onion and fresh, chopped parsley in a bowl.
2. Shape into 6 thick burgers.
3. Mix mayonnaise, Mrs. Dash® Tomato Basil Garlic and Dijon mustard in a small bowl.
4. Set aside.
5. Preheat grill to medium.
6. Remove stems from mushrooms and brush with a little water.
7. Sprinkle mushrooms with 1 Tbsp. (15mL) Mrs. Dash® Steak Grilling Blend™.
8. Place remaining Mrs. Dash® Steak Grilling Blend™ on a plate and pat burgers into it on both sides.
9. Grill burgers and mushrooms turning once or twice until the mushrooms are brown and tender and the burgers reach 160°F (71°C).
10. Grill buns until toasted.
11. Set a burger on a bun, top with a mushroom and spoon some sauce on top.
12. Cover with top of bun and serve immediately.