Big Mac Sloppy Joes (Instant Pot & Stovetop) - Six Sisters' Stuff

Ingredients

• ¾ cup mayonnaise
• 3 Tablespoons French Dressing
• 2 Tablespoons ketchup
• 2 Tablespoons dill pickle relish
• 1 Tablespoon minced onion
• 1 ½ teaspoon white vinegar
• 1 teaspoon sugar
• ⅛ teaspoon salt
• 1 ½ pounds lean ground beef
• ½ onion (diced)
• 1 teaspoon seasoned salt
• ¼ teaspoon ground black pepper
• ½ Tablespoon Worcestershire sauce
• 6 slices American cheese
• shredded lettuce
• pickles
• 6 Hamburger Buns (with sesame seeds, if desired)