Cauliflower with Sumac and Green Grape–Apple Vinaigrette

Green Grape–Apple Vinaigrette:

• 1 apple, peeled, cored, and cut into 1-inch pieces
• 1 tablespoon lemon juice
• 1 small bunch seedless green grapes, 
• 1/2 cup cilantro leaves and tender stems
• 1/2 cup mint leaves
• Half of a canned pickled jalepeño, drained, seeds removed, and roughly chopped
• 1/2 cup extra virgin olive oil
• Salt 

Cauliflower Steaks:

• 2 large heads cauliflower 
• 1/2 cup olive oil
• 2 teaspoons sumac
• Salt 
• Black pepper

Garnish:

• Half of a small red onion, thinly shaved
• 1/2 cup green seedless grapes, halved
• 1/4 cup toasted walnuts
• Torn cilantro and mint 
• Lemon wedges for squeezing

Make the green grape–apple vinaigrette: toss the apple pieces and the lemon juice together. Using a food processor, pulse 1 cup grapes and the apples to a slightly chunky purée, about 1 minute. Strain out the solids using a fine-mesh sieve, pressing down on the solids and reserving the liquid. Combine the herbs, jalapeño, and reserved liquid in the food processor and pulse to roughly chop the herbs, about 30 seconds. Add in the oil and pulse gently to combine. Season to taste with salt. 

Prepare the cauliflower steaks: place the cauliflower with the stem side sitting flat on a cutting board. Slice the cauliflower straight down into three 1-inch thick steaks. Keep as much of the cauliflower as intact as possible by making sure each steak has a little stem attached. Flatten the two end slices by trimming off the curved part. You want each steak to sit flat for even searing.

Brush each steak generously with oil on both sides and heat a medium sauté pan over high heat. Sear the cauliflower steaks until golden brown on both sides, about 2 minutes per side. Do this in batches, wiping the pan out with each new batch. Place the seared cauliflower onto a baking sheet and season each steak with sumac, salt, and pepper. Roast cauliflower until just tender, about 8 minutes. 

To serve, spread a thin layer of the green grape–apple vinaigrette on your serving plate. Arrange the seared cauliflower steaks on top. Garnish with the shaved red onion, halved grapes, toasted walnuts, the torn herbs, and a wedge of lemon.