Combine chicken with yogurt and tikka paste. Marinate for 1-2 hours, or overnight.
Cook the onion in oil until it is soft. Add the spiced chicken and cook until it is sealed.
Stir in the tomatoes, salt, and pepper. Off the heat, cool, and let simmer for 10 minutes.
Mix in the cream and the butter. After it cools completely, put it in a silicone bag and freeze it flat.
At camp, thaw a few hours in a pack or thaw partially in hot water.
Heat thoroughly, with constant stirring to prevent sticking, over a low single burner on the pot. 8–10 minutes.