Set your grill up for both direct and indirect heat grilling using a medium heat.
Place the sweet potato halves in a bowl and toss them in 1 tbsp of olive oil. Grill on direct side, flesh side down until they have grill marks, approximately 6-8 minutes. Turn over and move to the indirect side. Grill until tender, approximately 6-8 minutes. Remove from heat to cool. Cut into bite sized chunks.
In a large bowl whisk the remaining 3 tbsp oil, mustard, vinegar, oregano, capers, and chipolte flakes. Add the sweet potatoes, tomatoes, olives and parsley and gently mix all ingredients. Serve warm or cold.
For a different flavor try substituting 6 medium Yukon gold potatoes.