Prepare 9x13 baking pan with baking spray. Mix and bake cake according to package directions, replacing water with pineapple juice.
Once cake is baked and out of the oven, use the hand of a wooden spoon to poke holes into cake.
Combine pudding mix, milk, and run extract, and whisk for 1-2 minutes. Pour half into holes. Continue whisking 3 minutes until thickened slightly and spread over cake. Refrigerate 1-2 hours to set.
Spread on whipped topping and sprinkle toasted coconut on top. Add pineapple chunks and maraschino cherries for garnish. keep refrigerated until serving.