1. To prepare cakes, place quinoa in a fine sieve; place sieve in a large bowl. Cover quinoa with water. Using your hands, rub grains together for 30 seconds; rinse and drain well. Combine broth and quinoa in a small saucepan; bring to a boil. Cover, reduce heat, and simmer 20 minutes or until liquid is absorbed. Remove from heat, and fluff with a fork.
2. Combine 1 cup peas and 2 garlic cloves in a food processor; process until peas make a thick paste. Combine pea mixture, remaining 1 cup peas, panko, and the next 6 ingredients (through eggs) in a large bowl. Stir in quinoa. Divide mixture into 8 portions, shaping each into a 1/2-inch-thick patty.
3. Heat a large nonstick skillet over medium-high heat. Add 1 1/2 teaspoons oil; swirl to coat. Add 4 patties; cook 4 minutes on each side or until golden. Repeat procedure with remaining 1 1/2 teaspoons oil and patties. Keep warm.
4. To prepare greens, heat a large Dutch oven over medium heat. Add 2 teaspoons oil; swirl to coat. Add greens, beer, and next 4 ingredients (through 4 garlic cloves); bring to a boil. Cover, reduce heat, and simmer 30 minutes or until tender, stirring occasionally. Stir in vinegar. Serve with pea cakes; sprinkle with nuts.