Heat oil in a large skillet over medium heat.

Add the chicken cubes to the skillet.

Cook and stir the chicken until it is no longer pink, approximately 5 minutes.

Remove the cooked chicken from the skillet and set aside.

In the same skillet, add the chopped onion and minced garlic.

Cook and stir the onion and garlic until they soften, about 3 minutes.

Stir in the curry powder, cumin, cinnamon, and salt.

Add the lemon juice and diced tomatoes to the skillet.

Return the cooked chicken to the skillet.

Bring the mixture to a boil.

Reduce the heat to medium-low and simmer for 10 minutes.

Gradually stir in the half-and-half until well blended.

Serve hot with cooked rice or naan bread.