Pizza Panini with Chickpeas and Greens - Yummy Gusto

Ingredients

• 2 tablespoons unsalted butter
• 2 tablespoons extra virgin olive oil
• 0.5 cup finely diced yellow onion (approximately 1/2 small onion)
• 4 large garlic cloves, finely minced
• 850 grams cooked chickpeas (from two 425-gram cans), drained and rinsed
• 680 grams marinara sauce or spaghetti sauce
• 0.5 teaspoon dried rosemary
• 2 large handfuls mixed baby spinach, arugula, and/or kale
• Salt, to taste
• Freshly ground black pepper, to taste