Combine Dry Ingredients: In the bowl of a food processor, add the plain flour, grated cheddar, smoked paprika, 1/2 tsp of salt, and the onion powder (if using). Pulse 4-5 times to combine everything evenly.

Add the Cold Butter: Scatter the cold, cubed butter over the flour mixture. Pulse in short bursts, about 10-12 times, until the mixture resembles coarse breadcrumbs with some pea-sized pieces of butter still visible. This is crucial for flakiness.

Form the Dough: With the processor running on low, add the ice-cold water one tablespoon at a time. Stop as soon as the dough starts to clump together and form a ball. You might not need all the water. Be careful not to over-mix.

Chill the Dough: Turn the dough out onto a clean surface, gather it into a ball, and flatten it into a 1-inch thick disc. Wrap it tightly in cling film and place it in the refrigerator to chill for at least 30 minutes. This step is essential for resting the gluten and firming up the butter.

Preheat and Prepare: Towards the end of the chilling time, preheat your oven to 180°C (160°C Fan) and line two large baking trays with baking parchment.

Roll and Cut: Unwrap the chilled dough and place it on a lightly floured surface. Roll it out as thinly as you can, aiming for about 2-3mm thick. What works best for me is rolling the dough between two sheets of baking parchment; it prevents sticking and means no extra flour is needed. Use a pizza wheel or a sharp knife to cut the dough into small squares, roughly 2.5cm x 2.5cm.

Final Touches: Use a skewer or a chopstick to poke a small hole in the centre of each square – this helps them bake evenly and gives them that classic look. Carefully transfer the squares to your prepared baking trays, leaving a little space between them.

Bake to Perfection: Lightly sprinkle the crackers with a little extra fine sea salt. Bake for 15-18 minutes, rotating the trays halfway through, until the crackers are golden brown at the edges and feel firm to the touch. Keep a close eye on them in the last few minutes as they can brown very quickly.

Cool Completely: Let the crackers cool on the baking trays for 5 minutes before transferring them to a wire rack to cool completely. They will become much crisper as they cool.