Step 1

Begin boiling a pot of water for the noodles. Cook the noodles per package instructions as you prepare the sauce. (Frozen udon only needs a few minutes to cook, so I add them to the water when the sauce is almost ready.)

Step 2

Thinly slice the green onion, and separate the white and green portions. Dissolve the corn starch in the warm water.

Step 3

Set a skillet over medium to medium-low heat. Once hot, add the butter. Once the butter has melted, add the garlic and the white portions of the green onion. Cook, stirring frequently, until very fragrant, about 1-2 minutes.

Step 4

Add the gochujang paste to the skillet and mix vigorously until the gochujang is fully incorporated into the sauce. This step can be a little difficult, I like to use a flat whisk to make it easier.

Step 5

Once the gochujang is fully incorporated, turn off the heat and whisk in the corn starch and water mixture. If the sauce is too thick, you can add a little more water, one tablespoon at a time. If the sauce is too thin, put the skillet back over medium low heat and reduce until the desired consistency is reached. Taste the sauce and season with a little salt if desired.

Step 6

Add the drained noodles to the skillet and toss until they're fully coated in sauce. Transfer to your serving dish, top with sesame seeds, red pepper flakes, and green onion, then serve.