Start by boiling a pot of water and cooking the pasta according to package instructions. At the end of cooking the pasta set aside 1 cup of the pasta water before draining/straining the pasta.
Mix together the miso paste, soy sauce, reserved pasta water, sriracha, and sesame oil and set it to the side.
Mince the garlic and heat it in a pan with the olive oil over medium-low heat for 1-2 minutes until fragrant. Then pour the miso sauce mixture into the pan and continue to heat for several minutes allowing the sauce to thicken.
Mix the pasta into the sauce until well coated/combined and enjoy fresh.
Notes
You can store this pasta in a closed container in the fridge for up to 3 days. Add 1-2 tablespoon of water to the pasta when reheating it.