1. Preheat the oven to 375°. With a pastry brush or paper towel, spread a 12-by-18-inch jelly-roll pan with 2 teaspoons of butter.
2. Cream the butter and sugar together by beating them against the side of a bowl with a wooden spoon or by using an electric mixer set at medium speed.
3. When light and fluffy, beat in the eggs, 1at a time. Then beat in the flour and vanilla.
4. Spread the batter evenly onto the pan, sprinkle the surface with the almonds and currants and bake 20 to 25 minutes, until the surface is a light gold. Remove from the oven and let the cake cool in the pan.
5. With a sharp knife, cut into small triangles or squares.
6. These cakes, frequently served at Norwegian Christmases, can be made 2 weeks before the feast, but they must then be wrapped in aluminum foil or placed in an airtight tin and stored in a cool place.
