Preheat oven to 350 degrees F.
Prepare Pineapple Topping (see below).
In a large bowl, combine flour, sugar, baking powder, and salt. Add egg, milk, and vegetable shortening; beat 2 minutes. Add reserved 2 tablespoons pineapple syrup, lemon zest, lemon juice, and vanilla extract; beat 2 minutes.
Pour cake batter over prepared pineapple slices in the frying pan, spreading evenly.
Bake 40 to 50 minutes or until a toothpick inserted in center comes out clean. Cake is done when the internal temperature registers approximately 190 to 200 degrees F. on your cooking thermometer. Remove from oven and cool 5 minutes on a wire rack.
Run knife around edge of pan to loosen; cover with a cake plate and invert. Serve warm.
Makes 8 servings.
In a 10-inch cast iron frying pan or a 9- by 2-inch cake pan over low heat, melt butter. Stir in brown sugar until well blended. Remove from heat.
Drain canned pineapple, reserving 2 tablespoons pineapple syrup (for cake batter). Arrange drained pineapple slices onto top of sugar mixture. Place a maraschino cherry in center of each slice. Sprinkle with chopped nuts.
Set aside until ready to pour the prepared cake batter on top.
Pineapple Upside-Down Cake Recipe: https://whatscookingamerica.net/cake/pineapplecake.htm