Mix the dry ingredients: In a large bowl, whisk together gluten free flour, salt, garlic powder, and sugar until well combined.

Add wet ingredients: Create a well in the center of the flour mixture. Add olive oil, cold water, and beaten egg. Using a fork, gradually incorporate wet ingredients into flour mixture until a shaggy dough forms.

Knead briefly: Transfer dough to a clean counter and gently knead for 30 seconds until it comes together into a smooth ball. Don't overwork it.

Rest the dough: Flatten dough slightly, wrap tightly in plastic wrap, and refrigerate for 20 minutes. This allows the flour to hydrate properly.

Preheat and prep: Preheat oven to 375°F (190°C). Line 2 large baking sheets with parchment paper.

Roll the dough: Divide dough in half. On a lightly floured parchment sheet, roll one portion into a rectangle about ⅛-inch thick (3mm). Aim for even thickness throughout.

Cut into crackers: Using a sharp knife or pizza cutter, cut dough into 2-inch squares. Don't separate them - they'll break apart naturally after baking.

Transfer and repeat: Carefully transfer parchment with cut dough to prepared baking sheet. Repeat process with remaining dough portion.

Add toppings: Brush crackers lightly with olive oil and sprinkle with flaky sea salt or your chosen toppings.

Bake: Bake for 12 minutes, then rotate pans and swap their positions (top to bottom). Continue baking 8-12 minutes until golden brown and crispy.

Cool and separate: Remove from oven and cool on pan for 5 minutes. Carefully break crackers apart along cut lines. Transfer to cooling racks and cool completely.