This recipe is tried and true for me. I cut it out of Taste of Home many moons ago.
1/4 cup Dijon mustard
2 tsp paprika
1 tsp ground cumin
1 tsp chili powder
1/2 tsp salt
1/8 tsp cayenne pepper
2 lbs small red potatoes (I prefer red creamer potatoes, personally)
Spray a shallow roasting pan with cooking spray 3 times to coat well; set aside. Mix first 6 ingredients in a large ziplock bag. Cut any large potatoes into halves or quarters so all potatoes are roughly the same size. Pierce each with a fork. Shake potatoes in mustard mixture to coat. Place in prepared pan. Bake, uncovered, at 375 for 30-40 minutes until tender.