First, make the mole: In a heavy-bottom 2-quart saucepan, heat the olive oil over medium heat. Sauté the garlic, turning every minute until evenly browned. Add the onions, chillies, and tomatoes. Continue to sauté for 3 to 4 minutes, until the chillies and tomatoes are softened.
Drizzle the balsamic vinegar over the vegetables, then add the chicken stock, cloves, cinnamon, allspice, bread, cherries, currents, and apricots. Reduce heat and simmer, uncovered, for 15 minutes. Remove pan from heat, cover, and allow mixture to steep for 30 minutes.
In a blender, purée the mixture and strain, pressing on the solids to extract all the liquid. Return the strained sauce to the saucepan and whisk in the chocolate. If sauce is too thick, add 1 to 2 tablespoons of water to attain desired consistency. Set aside and keep warm.
Next, make the rub: Using a mortar and pestle, crush the peppercorns and the fennel seeds. Blend in the cumin, cinnamon, chilli powder, and salt. Liberally coat each fillet with the rub, reserving some for the pineapple and onions, then spray each fillet with olive oil. Spray the onion and pineapple slices with olive oil and sprinkle lightly with the remaining rub.
Place the salmon fillets and onions over Direct Medium heat for 10 minutes, turning once halfway through grilling time, or until the salmon is opaque and flesh flakes easily with a fork and the onions are nicely caramelised. Grill the pineapple over Direct Medium heat for 4 minutes, turning once halfway through grilling time. Remove salmon, onions, and pineapple from grill and keep warm.
Next, prepare the chard: In a heavy skillet, heat the olive oil over medium heat. Sauté the onion slices until just translucent, about 5 minutes. Add the chard and continue sautéing until chard is wilted, 2 to 3 minutes. Add in the vinegar, toss lightly, and season with salt to taste.
To serve, arrange the wilted chard and sautéed onions in the centre of each plate and place a grilled pineapple slice on top. Set a grilled salmon fillet on the pineapple. Garnish the dish with the grilled onion slices and the mole.