Pan fry the sausages if they are not already cooked. About 12 minutes over medium high heat turning occasionally.
Cut the pepper into 16 even sized pieces. Halve the onion horizontally, then halve one piece vertically. Separate the layers of the onion so you have 16 chunks of onion.
Toss the skewer ingredients in a bowl with the marinade and allow to marinate in fridge for 30 minutes or up to 24 hours.
Thread a skewer starting and ending with a Ciabatta cube. Alternate ingredients on skewer until you have 2 pieces of sausage, 2 mushrooms, 2 tomatoes, 2 pepper and 2 onion pieces and 2 basil leaves. Repeat until you have 8 skewers prepared.
You can grill immediately or you can put skewers into a sealable container and pour runoff dressing over the skewers. Skewers will hold up to 24 hours. Turn container periodically to redistribute the dressing.
Prepare BBQ grill. Grill skewer over medium low heat with lid down. Grill for 7-10 minutes turning skewers half way through. Cooking time may vary depending on heat of your grill. Check periodically. When mushroom are cooked and bread is crispy and golden or slightly charred remove skewers from the grill.
Serve over pasta, salad greens or on their own.