In a mixer with a paddle attachment, cream butter and sugar. Add the eggs one at a time, mixing well after each addition. Add vanilla extract and yoghurt and mix until just blended.

In a medium bowl, combine flour, salt, and baking powder well. Add to the mixing bowl. Blend dough on low speed until flour is well incorporated, scraping down sides of mixing bowl.

Turn out cookie dough onto a floured surface. Roll out dough to a ½-inch thickness. Cut with a 3-inch cookie cutter and place on a non-stick cookie sheet. Bake at 350°F for 13 to 15 minutes. Cookies should still be light in color but firm. Transfer cookies to wire racks and cool completely. Frost and decorate as desired.

Makes about 18 3-inch cookies.