Combine flour, semolina, seasoning, and salt in a large mixing bowl. Mix nicely with a spoon or fingers.
Pour oil and rub the flour mixture using your fingers to bring them together. The flour mixture should resemble fine bread crumbs
To bind dough, add ice cold water, one tablespoon at a time, and knead a stiff yet pliable dough. Knead the dough for 8 to 10 minutes.
Keep the dough covered aside for 10 minutes.
Preheat oven to 180 degrees celsius for 10 minutes. Line a baking sheet with parchment paper. Spray or brush it with cooking oil.
Divide the dough into two equal parts. Pick one ball at a time, and roll flat into ¼ inch thickness like a big sheet or roti.
Using a pizza or cookie cutter, cut squares. Prick each mathri with a fork and brush with oil. Sprinkle seeds on each mathri.
Bake them in a preheated oven, flipping once in between for even browning from both sides. It takes 20 - 25 minutes. Turn them halfway through for even browning and cooking.
Transfer the baked mathri to a wire rack to cool down. Once cooled, the mathri tends to crisp a little more.
Serve Baked Mathri immediately for storage in an airtight container.