Prep the chicken: Pat the chicken dry and season lightly with salt and pepper.
Cut into large bite-size pieces so they stay tender during slow cooking.
Build the flavor base: In the slow cooker, add onion, garlic, and ginger. Stir in curry paste (or powder), turmeric, cumin, coriander, and chili flakes. Mix until the aromatics are coated in the spices.
Make the sauce: Whisk together coconut milk, chicken broth, tomato paste, brown sugar, and soy sauce.
Pour this over the aromatics in the slow cooker and stir to combine.
Add the chicken: Nestle the chicken pieces into the sauce, making sure they’re mostly submerged.
Cook low and slow: Cover and cook on Low for 5–6 hours or High for 2.5–3.5 hours, until the chicken is tender and cooked through.
Add vegetables: About 45–60 minutes before the end of cooking, add your chopped vegetables. Stir, cover, and continue cooking until they’re tender but not mushy.
Finish with brightness: Stir in lime juice. Taste and adjust salt, sugar, or lime to balance the flavors.
If you want a thicker sauce, remove the lid for the last 20–30 minutes or stir in a slurry of 1 teaspoon cornstarch mixed with 1 tablespoon water.
Serve: Spoon the curry over hot rice or grains. Garnish with cilantro and an extra squeeze of lime. Serve with naan if you like.