Cut the chicken breast into slices (approx. 15 x 3 cm, 1 cm thick) and put on wooden sticks (water the wooden sticks over night to make sure, that the chicken comes off after cooking...).
Dissolve the tamarind paste in the hot water and add all the other ingredients for the marinade. pour over the chicken Satay and leave to soak for at least 2 hours or overnight.
Heat the coconut oil in a pan. Add the agave syrup and let it caramelize a bit. Now add the finely cut onions, garlic, chili and ginger and add a pinch of salt. Roast until the onion appears to be slightly golden. Add the crushed lemongrass stems and the warm water and bring to boil. Mix in the peanut butter and cook until creamy. Blend the sauce and season with soy sauce.
Grill the satays from both sides until golden and serve with the sauce. Basmati rice adds nicely to this dish.