Set oven to 350°F and line a muffin pan with 12 liners.
Whisk flour, sugar, baking soda, salt, and cocoa powder.
Combine almond milk, vinegar, oil, vanilla, and beet juice.
Blend wet and dry mixtures. Fill liners ¾ full and bake 18–20 minutes.
Beat butter and shortening, add powdered sugar and milk gradually, then color with beet juice.
Pipe buttercream and top with a glossy berry brushed with maple syrup.
