Pan should still have a considerable amount of oil/butter, add another 1tbsp if desired/needed. Get garlic and chicken broth ready and nearby the pan.
Add minced garlic and sauté for 30s-1min until fragrant. Be careful to not burn it! Add chicken broth and deglaze pan.
Add cream, lemon juice, grated parmesan, dry thyme, and stir. Bring to a boil then reduce heat to simmer, stirring regularly until slightly thickened, about 5 minutes.
Add a few handfuls of spinach and fold in until wilted. Add another couple handfuls until wilted but don't stir - I like to make a "bed" of spinach for the chicken to sit atop.
Place chicken thighs on top of the spinach/sauce, add in any accumulated juices from plate. Move pan to preheated oven and bake for 15 minutes or until instant-read thermometer reads 165°F.