For the mushrooms, White Button or Cremini (which is a brown button mushroom) work well. For those in Thailand, think White Shimeji or Buna Shimeji (brown) mushrooms or Shiitake mushrooms. For this recipe I used mostly Buna Shimeji and Shiitake mushrooms.
Slice/chop the mushrooms and cook in a non stick pan with 2 tablespoons of heated olive oil. Cook until lightly browned and softened and most of the water is cooked off. Drain.
Add the cooked mushrooms into a food processor and mince, or if grinding the chicken yourself, just run them through the grinder. If you really have time, mince yourself by hand if desired. (I course ground chicken thighs then simply ran the mushrooms through the grinder right after the chicken was run through.)
In a large bowl, add the chicken, the mushrooms, onion, eggs, panko, salt and pepper, mix to combine. I just used a large spoon, it mixes very easily.
Use an ice cream scoop to make perfect size small patties, hand shape into 2-3 inches across for fritters , or just make larger patties for say a sandwich roll.
In a large non stick pan, heat a splash of olive oil, add the patties, cover and cook about 3-4 minutes per side. When golden brown on each side, remove to paper towels to drain.
Serve with a dipping sauce of your choice, or if you make lager patties, enjoy on a sandwich roll with lettuce and mayo.