Heat oven to 400 degrees F.
Mix together garam masala, 1/2 teaspoon salt, 1/2 teaspoon of pepper, and oil; brush on chops. Toss potatoes with the remaining spice-oil mixture. Let chops marinate while potatoes roast.
Roast potatoes on baking sheet until tender and slightly browned (35 minutes). Smash some of the potatoes with a fork, making sure to leave some whole pieces. Stir in parsley plus one teaspoon salt and 1/4 teaspoon pepper.
Heat a cast-iron grill pan. When hot, sear chops and cook until medium rare (2-3 minutes per side). Set aside to rest.
Heat saute pan with one tablespoon canola oil; add green beans and remaining 1/2 teaspoon of salt and 1/4 teaspoon pepper. Cook one high heat until slightly charred.
Serve two lamb chops each with equal portions of potatoes and green beans.