Heat 1/4 cup olive oil in a medium skillet until moderately hot but not smoking. Add mushrooms and cook, stirring until softened and just beginning to brown. Remove from heat and set aside.
Heat remaining 1/4 cup olive oil in a large heavy pan until moderately hot, but not smoking. Add next seven ingredients. Stir in 1 tablespoon Ras El Hanout. Cook, covered over medium heat until partially cooked, about 10 minutes. Stir in 3 cups of vegetable stock.
Continue cooking until the vegetables are tender but not over-done, 20 to 30 minutes. During the last 10 minutes of the cooking, stir in the reserved portobello mushrooms and the chickpeas. Season with salt and pepper to taste. Cover to keep warm.
Rinse couscous in a sieve, add 2 tablespoons Ras el Hanout and salt, to taste. Let stand for 20 minutes, then separate the grains with your fingers.
Bring remaining 2 cups of vegetable stock to a simmer. Add couscous and cook over medium heat to steam and heat through.
To serve, mound couscous in the center of platter and surround with the vegetables. Garnish with mint leaves.
Mix together thoroughly.
In a small dry skillet over medium heat, toast caraway, coriander and cumin seeds until very aromatic, about 2 to 3 minutes. Shake the pan often to prevent burning. Remove from heat and let cool to room temperature. Grind to a fine powder in a spice grinder, coffee grinder, blender or with a mortar and pestle. Add garlic and salt and grind again until smooth. Add sweet paprika, red pepper flakes, mint leaves and olive oil and grind until the ingredients are well combined. The paste will be very thick and dry. Transfer paste to a small jar and cover with olive oil. Refrigerate for up to 6 months.