Mathematics educators frequently extol the virtues of inquiry-based instruction to classroom teachers. Although research suggests that inquiry benefits learners by allowing them to make sense of the mathematics they encounter, particularly through discourse with peers, to assume that all (or even most) teachers successfully create and implement inquiry-oriented lessons in their classrooms is wishful thinking. Teachers may incorrectly identify cookbook lessons--those that lead students through a series of procedural steps in a recipe-like fashion--as mathematical inquiry because students are active as they work through such tasks. Unfortunately, cookbook tasks give students few opportunities to develop their own methods of investigation or to realize the potential of mathematics as a creative area of study. Recognizing the unsatisfactory nature of recipe-oriented teaching materials, the authors share an approach they use with teachers to transform cookbook lessons into materials that more fully embrace the fundamental tenets of mathematical inquiry. (Contains 15 figures.)