The phrase "roll flat" is commonly used in the context of flat bread or pastry, but there are several synonyms that can be used interchangeably. For instance, you can use the phrase "flatten" when pressing dough or pastry to reduce thickness. Another synonym is "compress," which involves pressing the food with a rolling pin or other kitchen tool until it becomes thin and flat. Additionally, the terms "smash," "squish," and "mash" can be used to describe a similar action. Alternatively, the word "level" is also applicable when describing the process of rolling flat, as it refers to achieving an even and consistent thickness. All of these words are useful depending on the context of the situation and can convey slightly different meanings of pressure or evenness.