Vanilla extract is a staple in many baking recipes. If you don't have it on hand, or if you're just interested in experimenting a little, try almond extract as a substitute. It adds a hint of nuttiness, but it is a stronger flavor, so you need to use less than the amount of vanilla called for in the recipe. This replacement works best in recipes that are enhanced by vanilla, like cookies or cakes, rather than recipes in which vanilla is the prominent flavor, like ice cream or frosting. Simply prepare your recipe as directed, and add half the amount of almond extract in place of vanilla extract. (If the recipe calls for 1 teaspoon vanilla extract, only use 1/2 teaspoon almond extract.
When the baked goods are done, taste them and make a note of whether you'd prefer to use more or less almond extract next time.