The magic in this dish comes from perfectly toasted garlic. To achieve this gorgeous golden hue -- and avoid bitter burned garlic -- be patient.
Combine olive oil and garlic in a large skillet. Set over medium-low heat and cook, turning occasionally, until golden brown, about 6 minutes.
Remove garlic slices as they turn golden (they won't all brown at once) with a fork and drain on paper towels, leaving oil in pan.
Increase heat to high, add escarole, and season with salt and pepper. Stir to coat. Add stock. Cook until wilted.
Season with lemon juice, and drizzle with olive oil. Top with garlic chips.