Kanom Krok is an ubiquitous street snack made in the cast iron kanom krok pan. This version is rich, custardy and consistent. Recipes vary wildly, but this one works every time. More important than the recipe, though, is having a seasoned pan and even heat. I use a charcoal brazier, but you can use a gas burner that is wide and has a low temperature setting.
Mix all of the ingredients until the sugar is dissolved. You may have to add more rice flour after testing the batter.
Heat up the kanom krok pan. When it is hot, wipe the divets several times with a well oiled cloth.
The pan is ready when the batter is poured and it sizzles. The pan should not be smoking. Stir the batter and pour in 1 or 2 divets for testers. Cover and let cook for 5 minutes and check. The cake should be brown around the outside, but not burnt. Carefully take out the cakes by scraping around them with a spoon. If the cakes stick too much, add a tablespoon of rice flour and try again.
Stir the batter every time you make a batch, because the rice flour settles to the bottom. Make sure the divets are well oiled before making a batch.
Add a sprinkle of green onion to the cakes before covering. After the cakes are cooked, the hemispheres are usually placed on top of each other to make little spheres.