Peel, slice into 1/2" slices / rings and core fresh Pineapple. Grill or place rings under broiler on a sprayed sheet for 5 minutes each side or until lightly golden on edges. Set aside. (Can be done day/s before, and there is extra which I used for terriyaki chicken).
Melt 2 Tbsp Butter in 9" cake pan on stove. Stir in Brown Sugar, Cinnamon and 1 Tbsp water. When combined remove from heat and arrange as many slices as Pineapple you can fit flat on bottom of pan. Place halved Cherries in empty cores and corners of rings. Set aside.
In bowl mix Flour, Granulated Sugar and Baking Powder. Add Milk, 1/4 cup softened Butter, Egg, and Vanilla. Beat until combined scraping bowl. Spoon batter over rings and Cherries and smooth top carefully to cover.
Bake in a preheated 350 degree oven for 30-35 minutes or until a toothpick test comes out clean. Cool 5 minutes. Make sure sides are loosened and invert onto serving platter. Best warm, to warm cooled cake just needs 15-20 seconds in microwave.