Heat olive oil in a large Dutch oven over medium-high heat. Add chicken thigh pieces and brown on all sides for about 5-6 minutes total. Remove chicken to a plate and set aside.
In the same pot, add diced onion and cook for 3-4 minutes until softened and translucent. Add minced garlic and grated ginger, cook for another minute until fragrant.
Add cumin, curry powder, garam masala, coriander, and salt. Stir constantly for about 60 seconds to bloom the spices.
Pour in coconut milk and diced tomatoes with their juices. Stir well to combine and scrape up any browned bits from the bottom of the pot.
Return browned chicken to the pot along with carrots and baby potatoes. Bring to a gentle simmer, then reduce heat to medium-low.
Cover and simmer for 20 minutes, stirring occasionally. Add green beans during the last 5 minutes so they stay slightly crisp.
Remove from heat and stir in lemon juice. Let the curry cool completely on the counter for at least 45 minutes before portioning.
Portion cooled curry into meal prep containers and add cooked jasmine rice in a separate compartment. Label containers with the prep date.