Your substitute won’t be exactly the same. Heavy cream has a distinct silkiness. But your dish will be 90% as good—and 100% done. That’s a win.
Remember: Taste as you go. If your sauce feels thin, add more butter. If it feels too thick, splash in a little milk. You’re the boss. The half-and-half is just your employee.
So open that carton. Melt that butter. Stir with confidence. You’ve got this. Now go make something gorgeous—and don’t tell anyone your secret. They’ll never guess you started with coffee creamer.