Preheat oven to 350 degrees F. Coat a 1-quart casserole dish with cooking spray.
Cut assorted Martin’s rolls vertically into 1/2” slices. Brush with olive oil and bake 1-2 minutes per side on a baking sheet, until golden brown. Set aside.
In a medium bowl, combine spinach, cream cheese, Parmesan cheese, mayonnaise, lemon juice, ground red pepper, and garlic powder; beat until well blended. Stir in artichokes and spoon into prepared casserole dish.
Note: For a lighter version, use reduced-fat cream cheese and only 1/2 cup of Parmesan cheese.
Bake 30 to 35 minutes, or until heated through and the edges are golden. Serve immediately, with toasted roll slices for dipping.