- Melt butter in boiling water.
- Add flour, salt, and cream of tartar all at one time.
- Cook until mixture forms a ball that doesn’t separate.
- Remove from heat (try to give the dough "stretch" by scraping the dough across the pan as you stir).
- Beat in eggs, one at a time, until smooth.
- The dough should be stringy.
- If it does not stretch when pulled, add a few drops of water.
- Drop from a spoon on an ungreased baking sheet.
- Bake 20 minutes in preheated 425 °F oven.
- Let cool.
- Cut off tops and fill with custard or desired filling.