Cut grape tomatoes in half. Toss with olive oil, salt, chipotle pepper and ancho pepper and arrange in single layer on sheet tray.
Roast at 450ºF for 45 minutes, until tender and browned, stirring a few times; add parsley.
Slice polenta into 1/8-inch slices (or 24 per pound). Heat oil in large sauté pan on medium heat. Add several polenta slices and cook for 2 to 3 minutes until lightly browned and crisp. Turn and cook on remaining side. Remove from heat and drain on paper towels. Repeat with remaining polenta slices.
While polenta is cooking, combine sour cream, cream cheese, ground cumin and fine ground black pepper.
To assemble, spread each crispy polenta round with a dollop of the cumin spiced cream. Top with tomatoes and garnish with fresh parsley sprig. Best served at room temperature.