-
1
Heat 1 tablespoon oil in a medium nonstick skillet over medium heat.
-
2
Stir in onion and cook, stirring often, until brown, about 9 minutes.
-
3
Reduce heat to very low, season with salt and black pepper to taste.
-
4
Continue to cook, stirring often, until caramelized, about 15 to 20 minutes.
-
5
Transfer to a bowl and keep warm.
-
6
Meanwhile, place milk in a small bowl and place breadcrumbs on a large plate.
-
7
Dip each mushroom cap in milk, then dredge in the breadcrumbs.
-
8
Heat 1 tablespoon oil in a large nonstick skillet over medium heat.
-
9
Add mushrooms, gill-side down.
-
10
Place a heavy, heatproof plate or pie pan on top of the mushrooms and cook until golden brown, pressing down on the plate periodically to flatten them, about 6 minutes.
-
11
Carefully remove the plate using an oven mitt or tongs, add 1 tablespoon oil to the pan and turn the mushrooms over.
-
12
Replace the plate and cook, pressing the plate once or twice, until the mushrooms are golden brown and cooked through, 5 to 6 minutes more.
-
13
Remove from heat; cover to keep warm.
-
14
Heat the remaining 1 tablespoon oil in a Dutch oven over medium-high heat.
-
15
Add garlic and cook until fragrant, 20 to 30 seconds.
-
16
Stir in spinach and cook, stirring, until just wilted, 2 to 3 minutes.
-
17
Stir in beans, broth and season with salt and black pepper to taste.
-
18
Cook, stirring occasionally, until heated through, about 2 minutes.
-
19
Cut each mushroom into thin slices and serve over the spinach.
-
20
Spoon reserved onions on top and sprinkle cheese over.
-
21
Serve warm.
