Preheat oven to 400 degrees and line a baking sheet with parchment paper.
Combine the spinach, garlic, olives and sundried tomatoes in a food processor. Process until finely chopped. With the processor running, drizzle in the olive oil. Scrape down the sides and process again for a few seconds until a pesto/paste forms. Set aside.
Lay the puff pastry sheet on the parchment paper lined baking sheet. Using a rolling pin, roll it out a few times to flatten and even it out.
Spread the pesto (you'll probably have excess pesto left over) on the puff pastry covering the entire sheet except a 1 inch border around the sides.
Dot the goat cheese on top of the pesto.
Layer the tomato slices on top of the goat cheese in rows. Use the cherry tomatoes in between the larger slices.
Lastly, crumble the sausage on top of the tomatoes and season the whole thing with salt and pepper.
Bake for about 20-22 minutes until puffed and golden around the edges.
Remove from the oven and let cool for 5-10 minutes before slicing.