Preheat the oven to 400 F.
Invert a non-stick muffin tin. Lay 3 strips of bacon over each of 8 cups, overlapping slightly to cover the indentation. Place another inverted non-stick tin directly over the tin with the bacon to hold it in place. Transfer the tins to the oven and bake, upside down, until the bacon is set but still soft, about 10 minutes. Carefully remove the top tin and bake until the bacon is crisp and brown, about 5 minutes more. (You might want to put a sheet pan on the rack below the muffin tin to catch any dripping grease). Let the cups cool completely before removing them from the tin.
Following the instructions on the rice package for 1 cup uncooked rice, bring the water to a boil, and add the ginger coins. Let the water simmer a few minutes, and then stir in the rice. Cook as directed, then cover and let stand 5 minutes. Fluff with a fork and stir in the scallions, 2 tablespoons rice vinegar, teaspoon sesame seeds, nori, salt and pepper and mix well. Discard the ginger; cover and keep warm until ready to serve.
Meanwhile, remove the tops from the radishes and coarsely chop. Cut the radishes into small matchsticks. In a small bowl, whisk together the mustard, remaining 1 tablespoon vinegar, chopped ginger, olive oil, remaining sesame seeds, and salt and pepper until creamy and emulsified. Stir in the radishes and let stand about 5 minutes.
To serve, divide the chopped radish tops between 4 serving plates and drizzle them with a little of the dressing from the radishes. Put 2 bacon cups on each plate and fill each cup with about cup of the warm rice. Top the rice with a spoonful of the radishes and drizzle more dressing over the cups, if desired. Sprinkle each cup with a little more chopped nori and serve immediately.