Slice the cauliflower head into 1- inch steaks with the stem holding them together. You should be able to cut about 2 steaks slices. Set aside the remaining cauliflower florets for another cauliflower recipe.
Place the cauliflower steaks in a large saucepan with water and boil for 3-5 minutes until slightly soft. Drain and set aside.
In a large shallow bowl, mix the oat fiber (or almond flour) with the oregano, salt and pepper.
Dip the cauliflower into the dry mixture, coating each sides.
In a medium skillet or frying pan, heat the butter.
Cook the cauliflower steaks until golden on both sides for about 3-5 minutes. Set aside the cauliflower slices.
Add the garlic and shallots to the skillet and cook for 2 minutes until soft.
Add the stock, wine, lemon juice and rind. Simmer for about 5 minutes, stirring occasionally until the sauce slightly thickens.
Add the capers to the sauce, then return the cauliflower steaks to the pan. Spoon the sauce over them and heat for a couple of minutes.
Serve with a sprinkling of chopped parsley.