Cheesy Spinach-Artichoke Quesadillas

In a large skillet, heat 1 tablespoon olive oil over medium-high heat. Add garlic and 1/2 the shallot and cook until fragrant, 1 minute. Add spinach and cook until wilted, 3 minutes. Add artichoke hearts and red pepper flakes and cook 2 minutes. Season with salt and pepper. Transfer mixture to a strainer and push down with a wooden spoon (or paper towels) to remove any extra liquid. In a small bowl, stir together sundried tomatoes, remaining 1/2 shallot, parsley, red wine vinegar, and 1 1/2 tablespoons olive oil. Season with salt and pepper. Spread tortillas out on a clean work surface. Spread 1/4 of spinach filling on 4 tortillas and cover each with 1/2 cup cheese. Place remaining tortillas on top of filling. Brush outside of tortillas with remaining olive oil. Cook quesadillas in a large nonstick pan over medium-high heat until golden and cheese is melty, 2 to 3 minutes per side. Cut into wedges and serve.