Grab a medium pot and pour in the water. Add the gochujang, sugar, tomato paste, mushroom seasoning, coconut aminos, and sesame oil. Stir it all together until the sauce is nice and smooth. This pot is where all the magic happens, so make sure everything’s well mixed.
Now let’s talk mushrooms. Brush off any dirt and chop them into bite-sized pieces. Heat a pan with a splash of oil over medium-high heat. Once it’s hot, toss in the mushrooms and sauté until they start to brown and smell amazing. Add a quick splash of coconut aminos or soy sauce, then stir again to coat. Turn off the heat and let the mushrooms soak up all that flavor.
Add your beautifully browned mushrooms to the pot of sauce. Give it a stir so everything gets cozy together.
Rinse the rice cakes under cold water and gently pull apart any that are stuck. No need to soak them unless they’re super dry. Toss them into the same pot with the sauce and mushrooms.
Turn the heat on high and bring the pot to a boil. Once it’s bubbling, reduce the heat to medium and let it simmer uncovered. Stir occasionally so nothing sticks. After about 8 to 10 minutes, the rice cakes will start to soften and release starch, turning the sauce into a thick, glossy dream.
While it simmers, stack the perilla leaves, roll them up, and slice into thin ribbons. If you’re using sesame seeds or furikake, get those ready too.
Once the sauce is thick and the rice cakes are tender and chewy, turn off the heat. Transfer everything to a serving plate or bowl and top with your herb ribbons and sesame goodness.
Serve right away while it’s piping hot and the sauce is still clinging to everything. Don’t wait too long or the rice cakes will start to firm up. Trust me, it’s best enjoyed fresh and saucy!