Shoyu Mushroom & Spinach Pasta with Soy Sauce Koji

If you’re looking for a comforting vegetarian pasta that still delivers layers of flavor, this Shoyu Mushroom & Spinach Pasta is for you. Combining buttery mushrooms, earthy spinach, and umami-rich soy sauce koji, it’s a Japanese-inspired take on Italian comfort food.

Why It Works

Mushrooms and soy sauce koji are natural partners and both bring umami depth that makes every bite satisfying. Add fresh spinach, Parmesan, and a touch of black garlic (optional) for complexity, and you’ve got a dish that feels gourmet yet is ready in under 30 minutes.

Shoyu Mushroom & Spinach Pasta with soy sauce koji recipe (2 servings)

Ingredients

• 8 oz spaghetti

• 2 Tbsp butter

• 1 Tbsp olive oil

• 1/2 cup Parmesan cheese (shredded)

• 1 Tbsp Hakouya soy sauce koji

• 1 clove garlic, chopped

• 1 pinch dry chili pepper

• 4–5 mushrooms, sliced

• 1–1.5 cups spinach (cut into 2-inch pieces)

• 1/2 cup pasta water

• 1 clove black garlic (optional)

• Optional: chicken or seafood

Instructions

1. Cook pasta in salted boiling water until al dente. Reserve 1/2 cup pasta water, then drain.

2. In a skillet, heat butter and olive oil over medium heat. Add garlic and chili pepper, cooking until golden and fragrant.

3. Add mushrooms and cook for 2–3 minutes.

4. Stir in pasta water and soy sauce koji. Add spinach, pasta, and Parmesan, tossing well to coat.

5. Optional: garnish with thinly sliced black garlic before serving.

Serving Ideas & Variations

• Gluten-Free: Possible with GF pasta and soy sauce koji.

• Vegan Option: Swap butter for oil and Parmesan for nutritional yeast.

• Make it vegan: Use olive oil only (skip butter) and swap Parmesan for nutritional yeast.

• Extra protein: Add chicken, shrimp, or scallops.