The easiest version I know of is to buy a good box cake. I prefer orange cake or lemon cake, but you can use a plain yellow cake as well. Also have on hand whatever ingredients you need to make up the box cake, some butter, some candied cherries and some well drained canned pineapple slices.
Take a cake pan of the size specified in the instructions on the box, and grease well with butter. Make sure the bottom is fairly thickly smeared with butter, with just enough on the sides to prevent sticking.
Now, strew a good handful of light brown sugar evenly over the bottom. Here's where your sense of artistry comes in. Place the pineapple rings over the brown sugar, making a nice pattern. You can cut the rings into halves or even smaller pieces and make scallops, flowers, whatever. Use the candied cherries to add interest. You can also use pecans (make sure they are flat side up so the good side faces the bottom).
Mix up the box cake according to the directions and carefully pour over the pineapple. Bake as specified in the directions until a knife inserted in the centre comes out clean. Remove from the oven and let set for a few minutes (no longer) then run a thin bladed knife around the sides to loosen. Place your serving plate over the top and flip. Gently ease cake out of pan and let cool, or serve warm.
I usually line the bottom with a circle of parchment paper to assist with getting the cake out intact.
Hope that helps.