1. Spray the insert of a 6-quart slow cooker with cooking spray.
2. Place the pork chops in a large zip-top plastic bag and add the flour, steak seasoning, and salt. Close the bag and shake to coat the pork chops completely.
3. In a large nonstick skillet, heat 1 ½ teaspoons of the olive oil over medium-high heat. Remove the pork chops from the zip-top bag and brown in the skillet until golden brown, about 3 minutes per side. Reserve the bag o seasoned flour.
4. Transfer the pork chops to the slow cooker and arrange them in one layer over the bottom. In the same skillet, cook the onion over medium-high heat, stirring, for 2 minutes, until translucent. Add the remaining 1 ½ teaspoons olive oil and the mushrooms and cook, stirring, for 2 minutes more, until the mushrooms begins to brown. Sprinkle the onion and the mushrooms with the reserved flour mixture and cook until the flour has been absorbed, about 1 minute. Add the broth and cook, stirring, until the mixture comes to a boil and begins to thicken, 3 to 5 minutes.
5. Pour the mixture into the slow cooker over the pork chops, cover, and cook on Low for 3 to 3 ½ hours, depending on the thickness of the pork chops.
6. Server, garnished with fresh thyme.