Make the chicken stock for the ramen. Add the chicken bones to the instant pot and cover with water. Set the pressure cooker for 10 minutes. Release the steam and discard the water. Rinse the chicken bones and the instant pot and set the bones aside.
Heat 1 tablespoon oil in the pot of the instant pot. Add the chicken and sear on both sides until browned. Add back the chicken bones along with 1 quartered onion, 5 cloves garlic, and 8 cups water. Seal the instant pot with a lid and set the pressure cooker to 20 minutes. Remove the chicken and shred the meat. Close the lid and continue to cook the stock for 1 more hour.
Meanwhile, make the shio tare. Combine 1 cup water with a 3x3 inch kombu square in a medium pot. Cover and bring to a boil over medium-high heat. Reduce the heat to low and continue to simmer for 10 minutes. Remove from heat, add ½ cup bonito flakes and cover the pot. Let it sit for 10 minutes.
Strain the dashi broth, discarding the kombu and bonito flakes. Add 1 tablespoon salt, 2 tablespoon sake, and 1 tablespoon mirin. Bring the mixture to a simmer over medium heat until the salt has dissolved. Remove from heat and set aside.
Make the black garlic oil. Heat ¼ cup olive oil and 1 tablespoon minced garlic in a small saucepot over low heat. Continue to slowly cook the garlic until it turns almost black. Remove from heat and blend the oil until smooth. Set aside.
Prepare the remaining toppings for the ramen including soft boiled eggs and sauteed corn.
Release the steam from the pressure cooker. Strain the stock, discarding the chicken bones, onion, and garlic. Skim as much fat as possible.
Cook the ramen noodles according to the directions on the package.
Portion 1 ½ tablespoon shio tare into a bowl and ladle 2 cups ramen broth. Add 1 teaspoon MSG if using per portion and mix to combine. Add the cooked ramen noodles and top with chicken, egg, corn, and scallions. Drizzle black garlic oil on top. Serve immediately.