Preheat the oven to 425°F (220°C). Use the Simple Slicer on the #2 setting to slice the potatoes. Slice the tomato on #2 setting. Set the potatoes and tomato aside.In a medium bowl, combine the spinach, feta, garlic pressed with the Garlic Press, and salt. Mix well, breaking up larger pieces of feta.Place the chicken on one side of the Half Sheet Pan. Use the Large Scoop to divide the spinach mixture evenly onto the tops of the chicken. Use the back of the scoop to flatten the mixture. Place 3 tomato slices on top of each piece of chicken.In a small bowl, combine the panko with ½ tbsp (7 mL) of the rub. Sprinkle on top of the tomatoes.In a medium bowl, toss the potatoes with oil and the remaining rub. Place the potatoes on the other side of the pan and spread into a single layer. Spray the tops of the tomatoes with oil.Bake for 20–25 minutes, or until the internal temperature of the chicken reaches 165°F (74°C) and the potatoes are tender.Turn the broiler to HIGH. Place the sheet pan under the broiler for 1–2 minutes to lightly brown the panko. Remove the sheet pan from the oven.If desired, combine the Quick Tzatziki Sauce ingredients in the Measure, Mix & Pour®. Drizzle over the chicken and potatoes, or use it as a dipping sauce.