Combine the almond flour, salt, pepper, garlic powder, and Parmesan in a large bowl.
Add the avocado oil and mix thoroughly with a fork.
Add the ice water, 1 tablespoon at a time, and mix thoroughly, until small clumps form and the dough holds together when squeezed.
Form the dough into a round, flattening the top and bottom as evenly as possible.
Place the dough on a sheet of parchment paper and add another piece of parchment on top. Roll out the dough as evenly as possible, to between ¼- and ⅛-inch (6- and 3-mm) thick.
Remove the top layer of parchment paper and place on a baking sheet. You may need to press the edges of the dough to form an even rectangle.
Using a cookie cutter or pizza cutter, slice the dough to desired size. If using a cookie cutter, re-roll the excess dough and cut out more crackers.
If desired, use the blunt end of a skewer to poke holes in each of the crackers.
Carefully place the crackers on the baking sheet. If the dough is too warm, the crackers will break as you attempt to transfer them. Chill in the freezer for 10 minutes before proceeding if this happens.
Bake for 15-20 minutes, flipping halfway, until golden brown.
Let the crackers cool completely and serve as desired. Store up to 1 week at room temperature in an airtight container.