Mix the first 3 ingredients and gradually add 3 cups milk. Cook until thickened, use a double boiler.
Beat 3 egg yolks. Add to sauce in boiler slowly and stir. Cook for a few minutes, add butter and vanilla. Serve over warm yellow cake.
**If you're in a hurry, I've made the above recipe by following same basic steps but cooking in the microwave in a glass dish rather than on the stove. Microwave in 30 second increments and stir frequently.