Yes, you can substitute butter with ghee in samosas. Ghee, being clarified butter, offers a richer, nuttier flavor and a higher smoke point, which can enhance the samosa's taste and texture.
Ghee is essentially butter that has had its milk solids and water removed through a heating process. This process results in a pure butterfat with a higher smoke point than regular butter. When used in samosas, ghee contributes a distinct, slightly nutty flavor that many find appealing. It also tends to make the crust flakier and more tender. The higher smoke point is beneficial during frying, as it reduces the risk of the ghee burning and imparting a bitter taste to the samosas. You can use ghee in the same quantity as butter in your samosa recipe, both for the dough and for any fillings that require fat.
When using ghee, ensure it's properly melted but not too hot before incorporating it into the flour for the dough. Overheated ghee can alter the gluten development and result in a tougher crust.