In a pressure cooker insert, arrange chicken in a single layer. Add chipotle sauce, sour cream, and salt.
Close the lid and set the valve to the SEALING position. Pressure cook on HIGH pressure for 15 minutes (8 minutes if using chicken tenders).
When the Instant Pot beeps, do a natural release for 5 minutes and then QUICK RELEASE.
Open the lid and carefully shred the chicken with two forks.
Add the cheese and mix well.
In a dry skillet over medium heat, add corn tortilla and heat for about 20 to 30 seconds, turning as needed, until soft and pliable. Or cover the tortillas with damp cloth and warm in the microwave for about 30 seconds or until pliable.
Place tortilla on a flat surface and spoon about 1 to 1 1/2 tablespoons of chicken mixture on one end of the tortilla.
Starting from the end with filling, roll the corn tortilla around the filling into a tight log. Secure seam with toothpicks. Repeat with remaining corn tortillas and chicken mixture.
In a wide heavy-bottomed skillet over medium heat, heat about 2-inches deep of oil to 350 F.
Add the prepared taquitos in batches with seam side down and in a single layer. Fry, turning as needed, until golden and crispy.
Remove from pan and drain on wire rack. Serve immediately.