Bring butter to room temperature.

Add chopped cilantro, chopped garlic cloves, juice of lime and zest.

Stir well.

Using plastic wrap place butter on wrap and roll into a log of desired shape. (you can put in air tight container too) refrigerate until firm. You can place in freezer if in a rush.

While butter is firming up slice raw chicken into large bite size pieces.

Alternate chicken and onion on skewers, ending with an onion.

Do not push the meat and veggies too close together on skewers. Have them only very lightly touching. This allows the heat to cook the meat on all sides evenly.

Sprinkle salt and pepper on all sides of meat.

Pre-heat grill on med-high heat. When grill is heated, place skewers on distributed evenly. Flip when one side if gold brown with grill marks. Check temp before serving to test that chicken is throughly done.