Step 1

Soak farro in 6 cups cold water in a large bowl 1–2 hours (this will help it cook more evenly and in less time).

Step 2

Meanwhile, cook spinach in a large pot of boiling generously salted water just until wilted and bright green, about 45 seconds. Immediately transfer to a large bowl of ice water and swish around in water to cool down as quickly as possible. Drain spinach and gently squeeze to remove excess liquid.

Step 3

Blend spinach, ¼ cup oil, and ¼ cup water in a blender on low to break down spinach, then increase speed to high and blend until smooth, about 2 minutes. Pour through a fine-mesh sieve into a medium bowl; discard solids. Cover and chill spinach purée until ready to use.

Step 4

Drain farro and place in a large saucepan along with shallots, garlic, thyme, bay leaves, and 8 cups water. Bring to a boil over medium-high heat, then reduce heat and simmer gently, stirring occasionally, until farro is tender but still al dente (you don’t want grains to burst), 12–18 minutes. Drain, discard aromatics, and return farro to saucepan. Set a few peanuts aside for serving; coarsely chop remaining peanuts and add to farro.

Step 5

Preheat oven to 425°. Toss both mushrooms and ¼ cup oil in a medium bowl. Spread out in a single layer on a wire rack set inside a rimmed baking sheet (this lets heat circulate all around and helps the mushrooms crisp instead of steam). Season with salt and roast until mushrooms are browned, soft, and crisp around the edges, 25–30 minutes. Let cool slightly, then return to bowl and toss with 1 Tbsp. lemon juice; set aside.

Step 6

Add 3 Tbsp. water to farro and gently reheat over medium-low until just warmed through. Remove from heat and mix in just enough spinach purée to coat grains (you don’t want the mixture to be saucy; you’ll have some sauce leftover), then remaining 1 Tbsp. lemon juice. Drizzle with oil; season with salt.

Step 7

Spoon farro into shallow bowls and layer mushrooms over top. Drizzle with a little more oil; finely grate reserved peanuts over top.