Preheat oven to 375 degrees F.
Combine 1/4 cup of beer, orange juice, marmalade, zest and garlic in a small saucepan over medium heat. Whisk until the mixture comes to a boil, then reduce the heat to medium-low and simmer until slightly thick, for about 6 to 8 minutes.
Heat a large oven-safe skillet (I like cast iron) over medium high heat and add the olive oil. Season the chicken with the salt and pepper and add it to the skillet, searing on both sides until deeply golden, about 2 to 3 minutes per side. After the second side is seared, add the 1/4 cup of beer to the skillet and use a wooden spoon to scrape any bits off the bottom of the pan. Pour in the orange mixture and turn off the heat.
Place the chicken in the oven uncovered and bake for 20 minutes. Every 5 minutes, baste the chicken with the glaze in the bottom of the pan. Serve with greens.