Spray skillet with non-stick cooking spray. Heat 1 Tbsp olive oil over medium heat. Add garlic and cook until translucent about 1 1/2 min. Add the spinach and continue cooking until the spinach has wilted and all liquid has evaporated. Reserve and let cool. Lay the chicken breast flat, season with salt and pepper. Spread 1/4 of cooled spinach onto each chicken breast. Then roll the chicken into roulades away from you like a cigar. Wrap the roulades well with plastic wrap making sure to seal the side tightly. Steam or poach the chicken until the center reaches an internal temperature of 165°.
Place the cooked roulades in the refrigerator for at least 4 hrs or overnight. To make Crostini: Slice the baguette on a bias into thin slices. Place on a cookie sheet and sprinkle with 1 Tbsp of olive oil. Bake in oven until golden brown. Remove and reserve. In a medium mixing bowl, combine the tomatoes, onion, basil, and garlic in a large bowl, toss with the vinegar and oil to coat, and season with salt and pepper. To serve slice the chicken roulades into 1/2 inch rounds. To display simple top each crostini with one tablespoon of the tomato fresco and two roulades. Serves 8.