Start by browning the chicken thighs in a skillet over medium heat until the skin is golden and crispy, about 5-7 minutes per side. This step adds depth of flavor and aroma.
Transfer the browned chicken to the slow cooker, placing it in an even layer to ensure even cooking.
Sprinkle the grated ginger and chopped apple over the chicken, then pour in the curry powder and coconut milk, followed by the rinsed lentils and chicken broth. Stir gently to combine all ingredients evenly.
Cover the slow cooker with its lid and set it to low. Let it cook for 6 to 8 hours, during which the chicken becomes tender and the flavors meld into a fragrant, creamy stew.
After cooking, remove the chicken thighs and shred the meat with two forks, then return it to the stew. Stir gently to distribute the shredded chicken evenly throughout the thickened, fragrant broth.
Taste the stew and add salt and pepper accordingly. For a brighter flavor, squeeze in a touch of lemon juice if desired.
Serve the mulligatawny hot, garnished with fresh herbs if you like, alongside rice or crusty bread for a complete meal. Enjoy the comforting aroma and rich, silky texture with each spoonful.