This will likely be obtained over the course of the game just by playing normally. Personally, I obtained this playing level 3-3.
You will have to serve all possible combinations of ingredients and recipes to a customer that are new to this DLC. I've listed below all the new recipes added. The bets level for knocking these our is 3-2 with all of the combinations of burgers, drinks, and sides available. Donuts and Hot Dogs should more than likely be knocked out through natural gameplay since there are fewer combos.
Burgers
Beef Burger
Beef Burger + Red Drink
Beef Burger + Green Drink
Beef Burger + Yellow Drink
Beef Burger + Onion Rings
Beef Burger + Onion Rings + Cheese Curds
Beef Burger + Onion Rings + Fries
Beef Burger + Onion Rings + Red Drink
Beef Burger + Onion Rings + Green Drink
Beef Burger + Onion Rings + Yellow Drink
Beef Burger + Cheese Curds
Beef Burger + Cheese Curds + Fries
Beef Burger + Cheese Curds + Red Drink
Beef Burger + Cheese Curds + Green Drink
Beef Burger + Cheese Curds + Yellow Drink
Beef Burger + Fries
Beef Burger + Fries + Red Drink
Beef Burger + Fries + Green Drink
Beef Burger + Fries + Yellow Drink
Chicken Burger
Chicken Burger + Red Drink
Chicken Burger + Green Drink
Chicken Burger + Yellow Drink
Chicken Burger + Onion Rings
Chicken Burger + Onion Rings + Cheese Curds
Chicken Burger + Onion Rings + Fries
Chicken Burger + Onion Rings + Red Drink
Chicken Burger + Onion Rings + Green Drink
Chicken Burger + Onion Rings + Yellow Drink
Chicken Burger + Cheese Curds
Chicken Burger + Cheese Curds + Fries
Chicken Burger + Cheese Curds + Red Drink
Chicken Burger + Cheese Curds + Green Drink
Chicken Burger + Cheese Curds + Yellow Drink
Chicken Burger + Fries
Chicken Burger + Fries + Red Drink
Chicken Burger + Fries + Green Drink
Chicken Burger + Fries + Yellow Drink
Hot Dogs
Hot Dog
Hot Dog + Mustard
Hot Dog + Ketchup
Hot Dog + Mustard + Ketchup
Donuts
Honey Donut
Chocolate Donut
Berry Donut
EDIT
Thanks TheRealJoeSchmo and Sangriaz for adding some additional information that I updated the solution with.