1. Heat the oven to 425°. In a large nonstick frying pan, cook the sausage over moderately high heat, breaking it up with a fork, until browned, about 5 minutes. With a slotted spoon, remove the sausage from the pan. Pour off the fat from the pan.
2. Heat the 1 tablespoon oil in the pan over moderate heat. Add the potato, 1/2 teaspoon of the paprika, and the salt and cook, stirring occasionally, until tender, about 10 minutes.
3. Put four of the tortillas on a work surface. Put half of the sausage, potato, onion, cilantro, and cheese on the tortillas, spreading the ingredients all the way to the edge, and top with four more tortillas. Repeat with the remaining sausage, potato, onion, cilantro, and cheese and cover with the remaining four tortillas.
4. Brush the tops of the quesadillas with the remaining 1 teaspoon oil and sprinkle with the remaining 1/4 teaspoon paprika. Put the quesadillas on a baking sheet and bake until the cheese melts, about 5 minutes. Cut into wedges and serve.
Wine Recommendation: Many Portuguese reds have rustic personalities that will suit the mood of this dish well. The rich, hefty wines from the Dão or Douro regions are your best bets, but even the medium-bodied reds from elsewhere in Portugal have enough substance to stand up to chorizo.