01 -
Run the almond flour and powdered sugar through a food processor for 90 seconds. Sift everything well.
02 -
Start beating egg whites until bubbles appear. Slowly sprinkle in sugar while whipping to stiff peaks before adding color.
03 -
Gently fold the dry mix into the meringue. Stir until the mixture flows like thick syrup, about 35-40 folds.
04 -
Carefully pipe hearts using a guide. Bang trays to pop air bubbles. Wait 30 minutes or until surfaces feel dry.
05 -
Put trays in the oven one by one at 300°F for 12-15 minutes. Cool all the way before handling.
06 -
Beat butter for 2 minutes to make it creamy. Add sugar and salt bit by bit, then mix in lemon juice until it's fluffy.
07 -
Spread or pipe buttercream on half of the cookie shells. Top with another shell to sandwich them.