In a mixer, add melted butter, sugar, eggs, and vanilla.
Mix the flour with the baking powder and salt.
Change to dough hooks and add flour mixture.
Add the warm water and mix until it forms a smooth dough.
Make 11/2 inch balls with dough.
Roll balls out to about 4 inch worms.
Bring one end over the other, then underneath and through the middle, like a knot.
Place on baking sheet, four rows of four. (16 cookies on each sheet).
Bake in 350F oven for 13 - 15 minutes.
Let cool before icing.
To Ice: Mix all ingredients together in a bowl.
Add a little water until desired consistency.
Dip cookie upside down into icing, then turn over onto waxpaper.
Sprinkle with candy sprinkles.