Preheat the oven to 350°F & grease & parchment line 3-7" cake pans
Prepare the yellow cake recipe according to the instructions on that post & while the cakes are baking prepare the buttercream recipe as well
If you are making the daisy decor you will separate out ¼ cup buttercream for the yellow, ¼ cup for green & about 1½ cups white for the daisy petals
The rest of the buttercream is to be tinted a light yellow for the icing & building of the cake
Meanwhile prepare the pineapple topping by draining all the juice from the pineapple can into a small sauce pot along with the cornstarch & whisk completely smooth
Cook over medium high heat whisking constantly until it comes to a full boil
Remove from the heat & add the optional spiced rum extract & the vegan butter stirring until melted
Add the crushed pineapple to the cooked custard then transfer to a bowl or container to cool, reserve until ready to build the cake
Once the cakes are baked & completely cold build the cake as shown in the video tutorial