How you eat is how you live.
Let's eat well together.
Sign up for our useful and inspiring emails.
Get a $10 credit at Provisions,
our new kitchen and home shop, launching soon!
Well played.
You deserve a cookie.
We'll email you about claiming your credit and earning more by inviting friends.
Or Claim Your Credit Now
i would start by adding a few tablespoons of confectioner's sugar to see if you can bring it back together.
or, i would make a half-recipe of the frosting, adding in a little of the milk at a time, and mix in half of the old frosting.
it sounds like the butter and milk were too warm, or that you used too much milk. while you do need pliable butter, keeping milk at room temperature is risky with regards to spoilage. it's fine if it comes straight from the fridge.
I'm sorry I'm just seeing this now, but it sounds like you were in excellent hands (thanks vvvanessa!). Hope the icing turned out ok,