To make the dressing: Combine all the dressing ingredients but the olive oil and whisk together.
Slowly whisk in olive oil until emulsified. Set aside. Note: leftover dressing can be stored in the refrigerator for up to 2 weeks.
To make the bruschetta: Place the greens in large bowl. Add the tomatoes, sunflower seeds and dressing and toss to coat greens.
Spread the chevre on the bread, if you like, and top each slice with a few tablespoons of the greens mixture.