May we substitute butter for margarine please

I make with butter every time. But then I won't have margarine in the house either.

Agree on using the butter.
As margarine is usually about 100% fat and store-bought butter about 80%, using the same amount of butter will give a richer taste.
Or make with butter about 4/5 the volume called for margarine, and then add more at the table if wanted.

I make this as muffins, and yes, I use butter. It's delicious!