The ideal pumpkin for pie-making is the sugar pumpkin, also known as a pie pumpkin. These pumpkins are smaller, sweeter, and have smoother, less grainy flesh compared to larger carving pumpkins. The sugar pumpkin's flesh is well-suited for creating a smooth and velvety pumpkin puree, which is a key ingredient in pumpkin filling. While other pumpkin varieties can be used, sugar pumpkins are preferred for their flavor and texture, contributing to a more delicious and satisfying pie.