Preheat the oven to 350 degrees F. Place the Italian sausage in a large skillet over medium heat and saute for 5 minutes to brown. Break it into pieces with a wooden spoon. Once mostly cooked, push the sausage to the edge of the skillet and add the chopped, onion, pepper, and garlic. Saute another 3-4 minutes. Then mix in the sausage and remove from heat.
Meanwhile, bring a large pot of water to a boil. Once boiling add the DeLallo Organic Whole Wheat Penne to the pot and stir to separate. Cook the pasta for 5-6 minutes, until mostly cooked, but still firm. Drain the pasta in a colander.
Pour the marinara sauce into the pasta pot. Dump the drained pasta back into the pot and mix in the cooked sausage and veggies, along with the sliced pepperoni and olives. Mix well.
Dump the pasta into a 9x13-inch baking dish and spread evenly in the pan. Sprinkle the shredded mozzarella over the top and bake for 20-25 minutes, until the cheese is golden and bubbly. Serve warm.
Most of the ingredients in this dish are salty, so there is no need to add salt to the recipe. You can salt the pasta water, but do so sparingly.