NOTE: If you don’t have a skillet, I believe you can bake this in a greased 9-inch square baking dish (I’d use a glass one if you have it, and check it early and often. Remove when there’s some jiggle left.)
Make the crust: Preheat oven to 350 degrees. Whisk together cake flour and sugar in a medium bowl. Cut in the butter with a pastry cutter or two knives until the mixture resembles fine crumbs and starts to cling together. Press the mixture into the bottom (this step is a lot harder than it sounds, but be patient and use the back of a spoon to help spread/press the mixture down. I also stuck mine in the fridge for a bit to make the butter less sticky) and up the sides of a 10-inch cast iron skillet.
Make the filling: Cream together the butter and sugar until fluffy and pale yellow (about 2-3 minutes). Mix in the egg until just combined. Alternate adding the flour and evaporated milk, mixing after each addition. Mix in the corn syrup and vanilla. Pour the filling into the crust and sprinkle the top with icing sugar.
Bake and assemble the cake: Bake for 25 to 35 minutes or until cake is nearly set (mine was probably ready around 30). Some jiggle is fine — do not overcook! It’ll finish setting up as it cools. Let it cool in pan for 2 hours.
- Combine orange juice, sugar and champagne vinegar in a small saucepan over medium heat and bring to a boil. Cook for 15 minutes until reduced to about a half cup. Whisk in olive oil and salt and let stand for 2 minutes
- Combine blueberries, strawberries and peach slices in a large bowl. Add vinaigrette about 20 minutes before serving so that fruit is able to marinate...I think it tastes best if allowed to sit refrigerated until ready to use. Garnish with fresh basil leaves if desired.
In the meantime, beat heavy cream to stiff peaks. Pile heaps of fresh strawberries into the center of your cooled, set gooey butter cake, top with a mountain of freshly whipped cream or with the mixed fruit topping as listed in the recipe and serve.