In a dutch oven or large pot, heat 1 tablespoon of the olive oil. Add the chicken breast when the oil is hot.
Saute the chicken breast just until cooked through. Don't overcook. Remove the chicken from the pan and set aside.
Add the additional 1 tablespoon of olive oil to the pan, keeping it at medium-high heat. When the oil is hot, add the diced onions.
Saute the onions until translucent, about 3 minutes.
Add the garam masala, salt, ground ginger, and garlic to the onions.
Saute the mixture about 1 minute, until fragrant, at medium-high heat.
Add the chicken back to the pan with the spices, stir to coat the chicken with the spices. Once again, remove the chicken from the pan taking the spices and onion with it.
In the same pan (still on medium-high heat), add the canned tomatoes and coconut milk.
Bring the tomatoes and coconut milk to a low boil. Add the chicken mixture and heat through. Add the lemon juice and give a stir.
If desired, add the fresh cilantro to the whole pot. Not everyone in our family likes cilantro so we serve it as a garnish rather than adding it to the pot.
Serve with rice, naan, yogurt, and fresh cilantro.