Preheat a griddle or large, heavy skillet over moderately high heat. Combine the buckwheat pancake mix, beer and 1 teaspoon of the oil. Whisk until the batter is smooth. When the griddle is hot (a few drops of water sprinkled on the surface will sputter and dance about), brush lightly with some of the remaining oil. Pour about 1 tablespoon of batter per blini onto the griddle. When the bubbles appear on the top of the blini and the bottom is golden brown, 1 to 2 minutes, turn over and cook the other side until spotted brown, 30 to 60 seconds. Repeat with the remaining batter. Arrange the blini on a platter as they are cooked. Cut smoked salmon into 18 pieces. Top each blini with a piece of smoked salmon and a dab of sour cream. Serve immediately.