Combine all the sauce ingredients in a small saucepan and bring to a boil, stirring continuously. Once it has come to a boil, reduce heat to low-medium and simmer for 15 to 20 minutes, stirring occasionally. Simmer until it is a thick sauce, similar to oyster sauce. Pour into a container and set aside.

Preheat oven to 400 degrees Fahrenheit and line a baking sheet with parchment paper or a non-stick baking mat. Cut the cauliflower into medium sized florets. Try to remove as much of the stalk as possible. Put the cauliflower florets in a bowl and toss with a 1 tablespoon of peanut oil and 1/2 teaspoon salt until they are evenly coated. Spread the cauliflower florets onto the lined baking sheet and place in the oven. Roast for 20 minutes or until the forest begin to get brown along the edges. Let the cauliflower cool for ten minutes.

Take a small handful of cauliflower and place in a blender or food processor. I use a blender and you should be able to see the tips of the blades. Pulse for a few seconds on low speed (a 3 if you have a Vitamix). The cauliflower should have the texture of rice. Pour into a bowl. Repeat until you have "riced" all the cauliflower.

Bring a medium-sized pot of water to boil. Place the spinach in and keep there for 1 to 2 minutes. Drain. Squeeze excess water out of the spinach and place in a bowl. Add 2 teaspoons of sesame oil, 1/2 teaspoon of salt, and sesame seeds and mix well. Mix the cauliflower rice and the seasoned spinach together. Add 1 teaspoon (or more if desired) of the homemade Tankatsu Sauce and mix well. Add salt, pepper, and sesame seeds until the taste is right to you. Serve with Japanese Beef Curry.