Tuscan Stuffed Chicken with California Grapes and Squash Salad

For the California Grapes and Squash Salad:
1 Preheat the oven to 425F.
2 Place the sliced squash on a sheet plan lined with parchment paper. Drizzle with 1 tablespoon olive oil, season with ¼ teaspoon salt and ¼ teaspoon black pepper. Toss the squash to coat, spread the slices in a single layer, transfer to the oven and cook, undisturbed, until golden brown and tender, around 40 minutes. Remove the squash from the oven and set aside to let cool.
3 In a bowl, combine the Grapes from California, arugula, radicchio, shallot, almonds and roasted squash.
4 In a separate bowl, combine champagne vinegar, garlic, Dijon mustard, whole grain mustard, honey, 1/8 teaspoon salt and 1/8 teaspoon black pepper and whisk to combine. While continuously whisking, slowly drizzle in ¼ cup olive oil until fully emulsified. Taste the vinaigrette for seasoning and adjust with salt and pepper as desired.
5 Pour the vinaigrette over of the salad and gently toss everything to coat. Cover and set aside at room temperature until ready to serve.
For the Tuscan Stuffed Chicken:
7 Preheat the oven to 400F.
8 In a bowl, combine the chopped spinach, goat cheese, sundried tomatoes, crushed red pepper flakes, grated Parmigiano Reggiano, ¼ teaspoon salt and ¼ teaspoon black pepper. Mix until well combined, cover and transfer to the fridge for 15 minutes to slightly harden.
9 Using a sharp knife, make a deep incision along the length of the chicken breast, making sure not to pierce through the opposite side. Spread the chicken breast open to make a cavity and evenly stuff with the spinach and goat cheese mixture. Secure the edges with toothpicks or skewers and transfer to the fridge for 15 minutes to harden.
10 In a small bowl, combine the garlic powder, paprika, smoked paprika, dried thyme, ¾ teaspoon salt and ½ teaspoon black pepper and mix to combine. Remove the chicken breasts from the fridge, season with the spice rub and set aside.
11 Preheat an oven-safe pan over medium heat. Add 2 tablespoons olive oil and heat until shimmering. Carefully place the chicken in the pan and cook, undisturbed, until golden brown, around 4 minutes. Flip the chicken, transfer the pan to the oven and cook until the thickest part of the chicken registers 160F, around 15 minutes.
12 Remove the chicken from the oven, transfer to individual serving plates, drizzle with some of the pan drippings and serve alongside the California Grapes and Squash Salad.