Cook the couscous according to package directions. When adding water, also add juice from 1 lemon and salt/pepper to taste. Keep covered until serving.
Heat a large casserole pan on medium/high. Add olive oil, garlic, chile, basil, cumin seeds, and cinnamon. Stir and lay the fish fillets on top. Scatter the shrimp over the fish. Add the tomatoes and peas/beans. Squeeze in remaining lemon's juice.
Cover and bring to a boil. Reduce heat and simmer for about 8 minutes, or until fish is white and flaky.
Fluff couscous. Serve with stew over couscous; add basil leaves for garnish if desired.