Roasted leek, mushroom, and white bean casserole

When M. is out of town, I like to treat myself by cooking food that I like but he doesn't. Making the most out of a bad situation. Living large. Mushrooms feature prominently in my solo cuisine for this reason. I improvised this dish the other day and was very pleased with it. It is savory, flavorful, and healthy. Delicious! I even had it for breaknap today (meal before night shift - when one never decide between breakfast food or dinner food.)

Preheat oven to 425 degrees.
Trim, half length-wise, and clean 1 large leek. Slice into ~1/4" pieces. Clean carefully and thoroughly. I like to spread out the leaves under running water as they are often full of dirt.
Clean ~1 pint of baby bella mushrooms using a paper towel or a mushroom brush. Do not rinse - the water will soak into the mushrooms and make them chewy. Cut large mushrooms into 4 pieces and small ones into 2 so they're all roughly the same size.
Put these into two large baking pans along with 3 cups of white beans. Since you'll be roasting them, you want things to pretty much be in one layer.
Toss with a generous splash of EVOO (~2T per baking pan), a splash of balsamic vinegar (~1T per baking pan), a squirt of dijon mustard (~1T total), crushed rosemary (~1/2T total if you're using dried), white pepper (a shake per pan), and salt, to taste (~1/2t total).
Bake until mushrooms and leeks are lightly brown and beans are dry but not burnt (~30").
As soon as it comes out of the oven, sprinkle lightly with finely grated Parmesan.

I accompanied the above with mixed greens ("power greens") sauteed with a sliced leek, EVOO, lemon juice, salt, and white pepper.

I put both dishes into a bowl together and ate it with homemade white whole wheat rosemary bread. The next day, feeling in more of a breakfasty mood, I added a fried egg on top.

Mmm!