In small pot over med heat, combine 2 c of chicken stock and chutney, salt and pepper, bring to a bubble and keep simmering over low heat.
Heat large skillet or soup pot (with tight fitting lid) over med-high heat with oil. Add coriander, cumin, red pepper and "toast" spices for about 10 seconds. Add chicken and toss till well coated. Spread chicken in even layer and season with salt and pepper. Cook chicken pieces for 2 minutes each side till brown, then add onions, peppers, garlic and 3/4 ginger. Cook for about 3 minutes, stirring frequently. Add the remaining 1/2 c chicken stock. Cook 2-3 minutes, till most liquid is evaporated.
Create a well in the center of the pan, add the chicken stock/chutney mixture and lemon juice and zest Bring to a bubble, add couscous to center. USe a spoon to spread if necessary so couscous is all in liquid. REmove from heat and place tight fitting lid on the pan. Wait 5 minutes to cook couscous.
While the couscous is cooking, make sauce. In a blender combine yogurt, mint, cilantro, scallions, lime juice, remaining giner and a bit of water if necessary. Puree till smooth. Season with salt and pepper.
After cooking, fluff couscous with fork and remove to another pan to avoid sticking/clumping. Serve in shallow bowls with drizzles of sauce on top.