Cut ham and processed cheese into 1cm cubes.

In a bowl, mix okonomiyaki flour, water, and salad oil for dough by hand until combined. Knead for 5 minutes, cover with plastic wrap, and let rest at room temperature for 15 minutes.

Divide the dough into 6 portions, roll each into a ball, and flatten into 10–12cm circles. Place ham, cheese, and corn on each circle and wrap to seal. Repeat for all portions.