In a food processor, pulse the sun-dried tomatoes, 1 garlic clove, half of the jalapeño, 1/2 teaspoon of salt and 1/8 teaspoon of pepper until finely chopped. Add the bread crumbs and pulse to combine. Transfer the mixture to a large bowl and stir in the chicken, egg and milk. Using lightly moistened hands, roll the mixture into 20 meatballs, a scant 1 1/2 tablespoons each. (Mine were larger.) Dust the meatballs lightly with flour, tapping off any excess.
Wipe out the food processor and add the remaining garlic clove and jalapeño half; pulse until chopped. Add the tomatoes and their juices and the oregano and process until smooth.
In a 9-inch cast-iron skillet, heat the olive oil until shimmering. Add the meatballs and cook over moderate heat, turning, until golden but not quite cooked through, 5 to 6 minutes. Transfer to a plate. Add the tomato sauce to the skillet and simmer until slightly thickened, about 2 minutes.
Return the meatballs to the skillet and simmer, turning, until just cooked through, about 2 minutes longer. Transfer to a bowl, sprinkle with the parsley and serve.