Spotted this U-shaped tool with multiple metal blades in my grandmother’s baking bin. It has a wooden handle but looks like some kind of strange knuckles.

3. How A Pastry Blender Works To Cut Fat Into Flour
The primary function of a pastry blender is to cut fat, such as butter or shortening, into flour. This process is vital in creating a flaky texture in baked goods. The metal blades effectively break the fat into smaller pieces, which then become coated in flour. The goal is to achieve a mixture that resembles coarse crumbs or peas, indicating that the fat is evenly distributed.
This method helps to inhibit gluten formation, which occurs when flour and liquid are mixed. By limiting gluten development, the pastry remains tender and crumbly rather than tough. The pastry blender’s design allows for quick and uniform cutting, ensuring that the fat does not melt from the warmth of your hands.