Cook pasta in a large of pot of boiling, lightly salted water until just tender. While this occurs, heat oil in a large skillet set over medium-high heat. Add peppers and garlic and cook until just tender, about 2-3 minutes. Add artichokes, olives, tuna and stock and bring to a simmer. When pasta is cooked add it, a 1/2 cup (120 mL) of its cooking liquid, and the remaining ingredients to the skillet. Gently toss. Serve immediately.