Heat a pan with oil on a medium heat and place the chicken. Cook until the chicken is tender and cooked through. Add the butter if you want. This keeps your chicken moist and won't dry out.

When the chicken is fully done, you should be able to cut the thickest part of the chicken easily with a spatula or a butter knife. This is the indication it is fully cooked.

Lower the heat and add salt and all the seasoning. Stir fry just for a minute and turn off.

Cut or shred the chicken with a butter knife and spatula to smaller bits. Cool completely.

Meanwhile if you want, butter the bread slices on both the sides and toast until crisp. You can do this on a pan or in a toaster/ oven or air fryer.

To a mixing bowl add mayo, sour cream or Greek Yogurt (start with lower amounts). Stir in mustard, lemon juice, lettuce, cilantro, onions and the cooled chicken.

Stir well to mix. Taste test and adjust the seasoning to taste. The mixture must be moist but not runny.

Spread ¼ tsp mayo on the bread slice and place the lettuce, followed by the chicken filling. Cover with another slice of toasted bread.

Serve Chicken Sandwich.