Cheesy Brussels Sprout and Farro Bake

Maybe because I grew up on them (like so many of us did), I have a soft spot for casseroles, even though they’re hardly trendy these days. So, I am calling this a “bake” to keep up with the times, but truly, it’s the most delightful casserole I’ve eaten in years. Or, should I say, it’s a bit like a warm grain salad that’s held together with lots of melty Gruyère cheese and made browned and crisp on top with Parmesan. Toasted hazelnuts add crunch and balsamic and Dijon provide the right amou