Item Upgrades:
Except for Horchata Slot (drinks) which I upgraded to 2 stars the rest are all 3 stars. Do upgrade Taco fryer and slots first as that is the main. Burrito Oven Slot is also important.
Time Upgrades:
You only have 3 Taco Fryer and that is the main dish. So I upgraded it to 4 stars to decrease prep time. I also upgrade Burrito Oven to 2 stars and the rest are all 1 star.
Except for Horchata, Cinnamon Sticks, Ice Cream, and Honey, the rest all 4 stars. Do prioritise in this sequence: Taco, Prawns, Tomato Salsa, Beef, Cheese, Burrito, Pilaf, Pinto Beans, and Sopapilla.