Preheat oven to 350°F.

Prepare the pan: melt 2 sticks of unsalted butter and pour into a 12 x 18 x 3 pan.  Spread evenly over the pan.  Sprinkle the brown sugar evenly over the butter.  Evenly distribute the sliced pineapple (5 rows of 4) in the pan with a cherry in the middle of each ring.  Set aside.

Prepare the cake: In a medium bowl, whisk together all purpose flour, baking soda, and salt, set aside.

In a standing mixer fitted with the paddle attachment or in a large bowl with a hand mixer, beat the butter on medium high speed until pale and fluffy.  Scrape down the bowl if needed and add the sugar.  Beat on medium high until incorporated, about 1 minute.

With the mixer on low and eggs one at a time.  Add vanilla and sour cream.  Scrape down the bowl if needed and increase speed to medium, mix for 1 minute.

Working in two batches with the mixer on low, add ½ the flour mixture followed by half the milk.  Mix until incorporated and repeat with remaining ingredients.  Scrape down bowl if needed, increase speed to medium and mix until ingredients are smooth and incorporated (about 1 minute.)

Pour over prepared pan, spread evenly with spatula - some of the butter may pool up around the sides, if this happens spread more cake batter in that area but don't worry too much the edged of the cake should be buttery and gooey.  Bake on the middle rack in the preheated oven for 45 minutes.  The 'top' of the cake will brown slightly during baking and edges may crisp just a touch from the butter and brown sugar, but it is all part of the deliciousness!

Let cool 20 to 30 minutes before serving.  To serve, turn cake over onto a large cutting board or serving platter.  If the cake is turned over before the butter and brown sugar cool and thicken, it will leak all over the countertop.