1. Preheat oven to 350 degrees F.
2. In a large bowl, use an electric mixer on medium-high speed to cream butter until fluffy, about 5 minutes. Gradually beat in sugar, then one of the eggs. Batter should be pale yellow and fluffy.
3. In a medium bowl, sift together flour, baking powder, and cinnamon. Stir half the flour mixture into the butter mixture, mixing on low speed just until incorporated. Add yogurt and vanilla and mix well, then add remaining flour and mix on low until combined.
4. With well-floured hands, shape dough into walnut-size balls. Roll each ball into a rope about 6 to 7 inches long, fold in half, and twist, lightly pinching the end. Place twists on an ungreased baking sheet, about 1 inch apart (cookies expand slightly when baking). Lightly beat second egg. Brush cookies with beaten egg, then sprinkle with a large pinch of sesame seeds.
5. Bake for 16 to 18 minutes or until light brown. Cool on a wire rack, then store in an airtight container. May be frozen.
Source: Hannaford fresh Magazine, May - June 2009