In a large mixing bowl, add maida (all-purpose flour), semolina, ajwain, salt, pepper and oil. Mix using one hand such that the oil gets completely mixed in the dough.
Now add water as required little at a time to knead a firm dough (similar to puri). Knead for 6-7 minutes. Don't make the dough too soft, else the namak para will not be crunchy.
Now divide the dough into 4 parts and make balls. Roll out the dough thick (like a paratha, about 1/2 centimeter). Cut into diamond or square shapes.
Separate each diamond shape and keep aside in a plate. It is okay to keep them on top of each other. They will easily separate when frying. Roll again and repeat the process.
In a kadai/wok, heat the oil on medium-high flame. Then reduce the flame to medium. Dip the cut dough pieces in the hot oil. Fry while stirring frequently till the namak pare turn golden brown (about 4-6 minutes). You will need to make and fry them in multiple batches.
Take them out and lay them on a kitchen towel. When completely cool, serve or store them in an airtight container.