For the chicken: Make the marinade by adding all ingredients to a blender or food processor and blend until smooth. Pour marinade into a small saucepan and bring to a low simmer for about 5 minutes. Remove from stove and allow marinade to cool completely.
Place chicken thighs in a large storage bag and pour in half of the completely cooled marinade. Shake bag around to make sure chicken is fully coated. Place remaining marinade in a small sealed container in the fridge for later use. Let chicken marinade in the fridge for at least 30 minutes.
In the meantime, soak skewers in water to prevent from burning while cooking (if using wooden skewers). You'll need about 10-20 skewers.
To make the peanut sauce: Heat a small saucepan to low heat and add oil, ginger, onion and jalepeno. Cook until soft. Add garlic and cook another minute until fragrant. Add remaining ingredients to the saucepan and cook for another minute or two. Remove from heat and let cool. Pour ingredients into a blender and blend until smooth. Set aside for later.
Grill the chicken: Once the chicken is done marinating, slice into long skinny pieces. Place about 2-3 pieces of chicken per skewer. Heat the grill to medium-high heat. Lightly oil the grill to prevent sticking. Place skewers on the grill turning every 2-3 minutes until cooked through 165 degrees (about 15 minutes). Baste with remaining sauce during last few turns.
Serve skewers with warmed peanut sauce. Enjoy!