Preheat oven to 425°F. Add the pealed and sliced potatoes to a baking dish or sheet pan. Toss with olive oil, tikka masala seasoning, garam masala, and salt.
Bake potatoes for 30 minutes until softened and golden. In a large bowl, mix together Greek yogurt, tomato paste, garlic, olive oil, tikka masala seasoning, garam masala, and salt.
Add thinly sliced chicken breast and coat well in the marinade.Remove potatoes from the oven and spread the marinated chicken over the top.
Bake another 8–10 minutes, just until the chicken is cooked through.
Broil for 1–2 minutes for slightly charred edges if desired. Optional: Brush with melted butter before serving.