(Nutrition information is calculated using an ingredient database and should be considered an estimate.)
Preheat oven to 325 degrees. Cover a 9 x 12-inch baking pan with heavy duty aluminum foil and secure tightly. Cut small x's in the foil equally distanced in 3 columns and 4 rows, using a sharp paring knife.
Combine the oat milk and vinegar in a small cup and set aside.
In a medium mixing bowl, sift together flour, baking powder, and salt. Set aside.
In a large mixing bowl with an electric mixer or the bowl of a stand mixer, cream the Country Crock Plant Butter and sugar together until fluffy, about 2 minutes. Scrape down the sides.
With the mixer on low, add the vanilla extract, almond extract, and egg white, and mix until just combined, scraping down the sides as needed.
With the mixer on low, add the dry ingredients in two parts, alternating with the oat milk, scraping down the sides as needed and mixing until just combined (do not overmix - a few lumps are okay).
Add the rainbow sprinkles and gently fold in with a rubber spatula.
Fill each cone about halfway with cupcake batter and push each cone into the x openings in prepared pan. Bake on the middle rack for 32-35 minutes, until the center springs back when poked and a toothpick comes out clean or with just a few crumbs. Transfer to a wire rack to cool completely before frosting.
Buttercream Style Frosting:
In the bowl of a stand mixer or a large mixing bowl with an electric mixer, cream the butter until smooth. With the mixer on low, slowly add the powdered sugar, mixing until combined.
Add the vanilla and a tablespoon of oat milk at a time, mixing until smooth and spreadable. Fold in a few drops of gel food coloring, as desired.
Using a large star piping tip, pipe the frosting onto the cooled cupcake cones and top with more sprinkles.