Combine the quinoa and beef broth in a small saucepan and bring to a boil. Lower to a simmer, cover the saucepan with a lid, and cook for 14 minutes, or until all of the liquid has been absorbed. Let the quinoa rest, covered, for 5 minutes, then fluff with a fork.
Pre-heat the oven to 375 degrees.
In a small bowl, combine the Panko, sesame seeds and ½ teaspoon of the smoked paprika. Set aside.
Heat the olive oil in a large, 12-inch ovenproof skillet over medium heat. When the oil is hot and shimmering, add the onion and garlic, and cook for 4-5 minutes or until the onion is soft and translucent. Add the beef, salt, pepper, and remaining ½ teaspoon of smoked paprika to the skillet. Cook for about 7 minutes, stirring and breaking up the meat into small pieces with a spatula, until no longer pink. Stir in the tomato paste, mustard and Worcestershire and cook for 3 more minutes, then stir in the diced tomatoes.
Turn off the heat and fold in the cooked quinoa and ½ cup of the cheese. Smooth the top of the filling with a spatula. Add the remaining cheese in an even layer and sprinkle with the panko mix. Bake for 25 minutes until the cheese has melted and the topping is lightly browned.
Let your kickass quinoa bake rest for 10 minutes. (Trust me, it will be scary hot.) Serve topped with chopped lettuce and pickles.