Place chicken thighs in a large mixing bowl and season with salt and pepper.
Add the ranch dressing to the chicken thighs, mix to combine and set aside for about 10 minutes.
Heat oil in a large 4 to 5-quart saute pan, or a braiser, set over medium-high heat.
Add the chicken thighs to the hot oil and cook for 2 to 3 minutes per side, or until just browned; remove chicken from pan and set aside.
Return pan to heat; add the diced onions and peppers. If needed, add more oil.
Cook the onions and peppers for 2 to 3 minutes, or until just starting to soften.
Stir in the garlic and cook for 15 seconds.
Add frozen mixed vegetables and rice; stir and cook for 1 minute.
Pour in the chicken broth and gently stir to combine.
Arrange chicken thighs over the rice; sprinkle paprika over the chicken thighs and rice.
Lower heat to medium; cover the pan and cook for 18 to 22 minutes, or until liquid has evaporated, and rice and chicken are cooked through.
Remove from heat.
Fluff up the rice with a fork. Taste for salt and pepper, and adjust.
Serve.