1. Preheat oven to 300°F (180°C).
2. Line two cookie sheets with parchment paper or lightly oil.
3. In a bowl, cream butter and sugar until light and flurry. Stir in vanilla. Add nuts and flour, stir until evenly blended.
4. Roll into small balls, 1-inch (2.5-cm) in diameter, and place on cookie sheets about 2 inches (5 cm) apart. Bake in oven for 30 to 40 minutes, or until lightly golden.
5. Place confectioner's sugar on a small plate. While baked puffs are hot, roll them in sugar.
6. Roll again in sugar when cold.