The term SNACK IN A SHELL can be summarized by two crossword solutions: TACO (4 letters) and PECAN (5 letters). A taco is a traditional Mexican dish consisting of a corn or wheat tortilla filled with various ingredients such as beef, pork, chicken, vegetables, and cheese. It is often served with salsa, sour cream, and guacamole. Pecans are a type of nut native to North America and are commonly used in baking and cooking. They are also eaten as a snack on their own or in combination with other ingredients.