Here is what you do, using the same ingredients but not using a crock pot. I"m indian and i never use one for chicken curry dishes:
1.) saute onions, giner and garlic in oil until tender under medium high heat, add tomatoes, garam masala, salt, pepper, cumin, coriander, brown sugar and cook down t until mushy.
2.) Add chicken to the mix and 1/2 cup of water
3.) cover and cook for 20 min on med high
4.) remove lid, add yogurt and cook uncovered on med for another 20 min.