Step 1

Make the quick-pickled onions. To a jar or small bowl, add the red onion, 3 tablespoons apple cider vinegar, 1 tablespoon honey, 1 tablespoon of the tarragon, and 3 tablespoons of water. Season with ½ teaspoon salt, cover, and vigorously shake well (or stir to combine if using a bowl). Set aside to let the flavors meld for 30 minutes, shaking or stirring every 10 minutes. Reserve 2 tablespoons of pickling liquid in a mixing bowl for the dressing, then drain the onions and set aside.

Step 2

Meanwhile, toast the nuts. In a dry medium skillet over medium heat, add the walnuts. Cook, tossing occasionally, until the nuts are lightly toasted, about 6 minutes, then transfer to a plate to cool.

Step 3

Make the dressing. To the mixing bowl with the pickling liquid, add the Dijon mustard, red pepper flakes, remaining 2 teaspoons honey and remaining 2 tablespoons apple cider vinegar. Season with 1/2 teaspoon salt and 1/2 teaspoon black pepper and whisk to combine. Set the bowl near your stovetop.

Step 4

Get the spinach ready to be dressed. In a large bowl, add the baby spinach. Have some cling wrap close by (or a tight-fitting lid for the bowl).

Step 5

Warm the dressing. Give the skillet you used to toast the walnuts a quick wipe with a paper towel if there’s any residue. Return it to medium heat and warm the olive oil until shimmering. Add the garlic, stirring continuously until fragrant, 1 to 2 minutes. Over the heat, vigorously whisk in the dressing mixture until emulsified. Whisk continuously until the dressing is hot and bubbling at the edges.

Step 6

Wilt the spinach. Remove from heat and pour the dressing over the spinach, keeping about 2 tablespoons in the skillet. Immediately cover the bowl well with plastic wrap or a lid. Give the bowl a shake to toss the spinach in the dressing. Set the covered bowl aside to allow the dressing to warm the spinach.

Step 7

Warm the cannellini beans. Add the beans to the remaining dressing in the skillet and set over medium heat. Carefully stir occasionally (making sure you do not mash up the beans) until the beans are hot, about 2 minutes.

Step 8

Season the beans. Turn off the heat and quickly stir in the lemon zest, 1/4 teaspoon salt, and 1/2 teaspoon pepper. Immediately add to the bowl with the spinach (do not stir) and quickly cover with plastic wrap to help retain the heat, giving the bowl a shake to toss the beans and spinach. Allow to sit for 3 minutes.

Step 9

Assemble and serve the salad. Transfer the spinach and cannellini beans to a serving platter or salad bowl, layering them with the pickled red onions and goat cheese. Top with the toasted walnuts and a sprinkle of fresh tarragon (I used about 2 teaspoons). Serve immediately.