Cream the butter. Add the sugar, egg and vanilla and mix well. In a separate bowl, mix together the flour, almonds, poppy seeds and salt. Gradually add to the butter mixture and beat well. Divide the dough in half and roll into logs. Roll the logs in colored sugar. Wrap in waxed paper and chill for a few hours.
Preheat oven to 325 degrees. Slice the logs about 1/4-inch thick and bake for about 12 minutes or until the edges start to brown.