Season chicken thighs with salt and black pepper.

Place chicken in the bottom of a large skillet.

Combine ketchup and cola in a medium bowl and mix.

Pour mixture over chicken.

Heat chicken and sauce until sauce starts to boil.

Reduce heat and simmer, covered, for 40 minutes, stirring occasionally to prevent sticking.

Uncover chicken and continue simmering for 10 or more minutes, stirring once or twice, until sauce thickens.