Cook the udon noodles. Bring a large saucepan of water to a boil. Once boiling, salt generously (2 to 3 teaspoons kosher salt) and add the bundles of udon noodles. Cook for 1 minute, then use a chopstick or tongs to loosen and separate the noodles. Cook for another 1 minute, for a total of 2 minutes until chewy but tender. Drain in a colander and rinse with cold water until cool. Shake the colander well to drain.
While the water is boiling, mince the garlic, chop the peanuts and cilantro, slice the bell peppers, and scallions. In a bowl, toss the edamame with the sea salt.
Make the Garlic Chili Oil. Add the chile flakes, sesame seeds, garlic, and peanuts to a small-medium bowl. Heat the oil in your smallest saucepan over medium heat until hot and shimmering, 3 to 5 minutes. Pour the hot oil over the garlic-peanut mixture. Stir and let sit for 1 minute. Stir the soy sauce, vinegar, and maple syrup or agave into the garlic-chili oil.
Pour only HALF of the chili oil-soy sauce mixture over the noodles; reserve the rest for another recipe. Add the bell peppers, edamame, cilantro and scallions, and toss really well. Serve at room temperature, or chill in the fridge if desired.
