1. For crust, melt butter in a 9-inch glass pie plate in microwave oven (about 45 seconds at High). Add cracker crumbs and cinnamon; mix well with a fork. Press crumb mixture evenly onto bottom and sides of pie plate. Cook uncovered in microwave oven 2 minutes at High; rotate pie plate one-quarter turn halfway through cooking period. Remove from oven and set aside.
2. For filling, soften cream cheese in a small glass bowl in microwave oven (about 1 minute at High). Add 1/4 cup sugar, 1/2 teaspoon vanilla extract and the egg to cream cheese; mix until well blended. Pour filling into crust.
3. Cook uncovered in microwave oven 3 minutes at Medium-High, or
until bubbles appear on surface; rotate pie plate one-quarter turn once. Remove from oven and cool slightly.
4. Blend sour cream, 2 tablespoons sugar and 1/2 teaspoon vanilla extract. Spoon sour cream mixture over filling. Cook uncovered in microwave oven 2 1/2 minutes at Medium-High, or until set. Cool, then chill thoroughly.