Mix together the ground beef, steak seasoning, and Worcestershire sauce. Form into even patties. Transfer to a plate, cover with plastic wrap.
Make the olive sauce: Mix olives and mayonnaise for olive sauce, and allow to chill in the refrigerator until serving time.
Prep the batter: Combine flour, cornstarch, kosher salt, baking powder, paprika, and a few grinds of pepper in a large bowl then whisk to combine.
Heat a grill or grill pan over medium heat.
Lightly toast the buns in a toaster oven or briefly place flat side-down on the grill.
Cook the burger patties: Add the patties to the grill and cook on both sides, to your desired internal temperature using a thermometer (see below).
Compose the burger: Place patties on bottom buns, top with olive mixture, close burgers with top buns.
Toss the onion rings in flour and then dip into the batter (working in small batches if necessary). Working one at a time, pick up the onion ring and allow excess batter to drip back into the bowl. Carefully lower it into the hot oil. Repeat with remaining rings until deep golden brown and crispy.
Serve: Enjoy your michigan burger with onion, and light beer.