In a large bowl, whisk together the flour, sugar, salt, onion powder, garlic powder, and rosemary (or other add-ins). Pour in the water and olive oil and stir with a wooden spoon or silicone spatula until the dough comes together in a clump.

Turn the dough out onto a lightly floured work surface. Lightly flour your hands and the dough and knead it, sprinkling on a little more flour as you go, until it’s no longer sticking to your hands and you can shape it into a rough ball, about 1 to 2 minutes. Return the dough to the bowl and cover the bowl with plastic wrap. Let the dough rest for at least 10 minutes, and up to 1 hour at room temperature.

Preheat the oven to 425°F (218°C) and line large silver baking sheets with parchment paper.

Cut the dough in half. Keep one half of the dough covered while you work with the other half.

On a lightly floured work surface with a lightly floured rolling pin, roll one half of the dough out into a rectangle. Roll the dough very thin—about 1/16th of an inch (1.5mm). If the dough keeps shrinking back as you try to roll it out, lightly cover it and let it rest for 5 minutes, then try again. (Don’t worry if it shrinks, that’s completely normal and expected.)

Using a ruler and a pizza cutter, cut the dough into small rectangles about 3 x 1.5 inches in size. Carefully transfer the crackers to the prepared baking sheet(s).

Repeat steps 5 and 6 with the second half of dough.

Dock (poke holes in) the crackers several times with a fork. Brush with olive oil, then sprinkle with flaky sea salt (and everything bagel seasoning or sesame seeds, if making those varieties. Note that extra seasonings on top can sometimes fall off of the crackers when eating them).

Bake until golden brown and crispy, about 9–12 minutes. To ensure even browning, rotate the baking sheet(s) halfway through baking.

Let crackers cool completely on the baking sheet(s) set on a cooling rack. Crackers need several minutes of cooling before they taste crispy. They taste fantastic with hummus, crab dip or other dips, various cheeses, or serve with a cranberry pecan cheese ball.

Store in an airtight container at room temperature in a dry place for up to 2 days. To re-crisp crackers, spread them on a baking sheet and bake at 350°F for 10 minutes. Cool completely before serving.