Why is your tart shell too hard?
There are a number of reasons a tart shell could become hard. Too much flour might have been added or worked into the dough while rolling or shaping. It may have been handled and worked too much which could have "worked up" the gluten in the dough. The tart shell may have been baked too long at too low a temperature or simply baked too long.
If I understand your question correctly, you are asking if you can use a baked, fully prepared pastry (pie crust) to mix with other ingredients to make a tart shell. If so, then the answer is no. You would do better by just using the one that is already made for the tart shell instead of trying to crumble it and mix with other ingredients to make a new one.
Hard cooked (or hard boiled) eggs can be difficult to peel if they are improperly cooked. Cooling them very quickly after cooking them can often make the peeling easier. Cooking them too long can make peeling more difficult. The problem with peeling hard boiled eggs is that there is some tendency for the egg to stick to the shell, so that when you are peeling off the shell, you get egg coming off with the…
Soft shell crabs are soft and are eaten with the entire crab. Soft shell crabs are actually hard shell crabs that have shed their shells to allow for growth. Shells do not grow with the crab. Crabs retain a soft shell when they shed their hard shells; then that soft shells begins to harden-up as the crab grows.