potato and artichoke tortilla

INGREDIENTS

• About 4 tablespoons olive oil, plus more if needed
• 1/2 medium-size onion, quartered and thinly sliced
• 1 large boiled Yukon Gold potato, quartered and thinly sliced (a leftover potato works great here)
• 3 marinated artichoke hearts (from a can or jar), rinsed, patted dry, and thinly sliced
• 1/4 cup sliced piquillo peppers or roasted red bell peppers
• 4 large, very fresh eggs, preferably organic
• 2 tablespoons chick stock or broth
• Coarse salt (kosher or sea)