Pat the chicken legs dry with paper towels.
In a small bowl, mix together salt, black pepper, smoked paprika, garlic powder, onion powder, dried thyme, and cayenne pepper.
Rub the spice mixture evenly over all sides of the chicken legs.
Heat olive oil in a skillet over medium-high heat.
Sear the chicken legs in the skillet for 2-3 minutes on each side until golden brown.
Transfer the seared chicken legs to the slow cooker.
Pour the chicken broth into the slow cooker around the chicken legs.
Cover and cook on low for 6 hours or until the chicken is tender and cooked through (internal temperature should reach 165°F / 74°C).
Once cooked, remove chicken legs from the slow cooker and let rest for 5 minutes before serving.