"Receipt" and "recipe" are synonyms, according to the Oxford English Dictionary. What causes some confusion is that "receipt" is considered an archaic word, but there's no error if one choose to use it. Some examples from the Oxford Dictionary:
"She spent hours in the kitchen, trying all sorts of receipts"
"The Ohio testers found that most of the receipts can be made easily with present-day ingredients, techniques, and equipment."
"Romans have always loved eating well (Apicio, who lived in the I century A.D. left a lot of cooking receipts) and today Roman dishes are considered Italian dishes."