In a large mixing bowl, combine the all-purpose flour, granulated sugar, baking powder, and salt. Mix well.
Add the chilled butter pieces and use your fingers or a pastry cutter to blend the butter into the flour mixture until it resembles coarse crumbs.
Gradually add the water, a little at a time, mixing until the dough comes together. You may need to add a little more water to achieve the right consistency. The dough should be soft but not sticky.
Turn the dough out onto a lightly floured surface and knead for about 5 minutes until it is smooth and elastic. Cover the dough with a damp cloth and let it rest for about 15 minutes.
Divide the dough into small balls, about the size of a golf ball. Flatten each ball into a disk about 1/2 inch thick.
In a large skillet, heat about 1 inch of vegetable oil over medium heat until hot.
Carefully place the dough disks into the hot oil, a few at a time, being careful not to overcrowd the skillet. Fry until golden brown on one side, about 2-3 minutes, then flip and fry the other side until golden brown and cooked through.
Remove the johnny cakes from the oil and drain on paper towels to remove excess oil. Serve hot.
Enjoy your meal!