Preheat oven to 350 degrees Fahrenheit (180 degrees Celsius). In a frying pan, sauté onion in oil until translucent and beginning to brown. Transfer to a large mixing bowl; add potatoes and mash until smooth. Stir in egg and season generously with salt and pepper. Place broccoli (or any preferred vegetable filling) in a separate bowl and mash until smooth. (You can also blend potatoes and then broccoli in a food processor, for a creamier consistency — either way is fine.)

Place ground almonds in a dish. Place a heaping tablespoon of potato mixture onto almonds, top with a tablespoon of broccoli mixture and then cover with another heaping tablespoon of potato mixture. Carefully roll the “pile” in almonds, forming into a coated ball. Repeat with remaining mixture.

Place balls onto a greased 9×13-inch baking pan. Spray with oil spray and bake, uncovered, for 30 minutes.