Combine instant potatoes, sugar, water, and yeast in a covered container or zip top bag. Let the starter sit on a counter for 5 days, stirring daily with a wooden spoon, or just mush the bag really well to blend ingredients.

On the morning of the fifth day, feed the starter with 3 tablespoons instant potatoes, 3 tablespoons sugar, and 1 cup warm water. That evening, take out 1 cup of the starter to use in a sourdough recipe. Refrigerate the remaining starter.

Every five days, feed the starter 3 tablespoons instant potatoes, 3 tablespoons sugar and 1 cup water.

TO USE STARTER IN RECIPE: let the fed starter rest at room temperature 6 hours before use.

If starter is not being used in a recipe, keep refrigerated and discard 1 cup of starter after each feeding.