01 -
Using your hands or a mixer, tear the cooked chicken into small, manageable bits.
02 -
Blend the mayo, sour cream, mustard, salt, pepper, onion powder, garlic powder, and lemon juice in a bowl until they're smooth and combined.
03 -
Mix the sauce with the shredded chicken. Stir in the green onion, celery, dill, pickles, and walnuts until combined.
04 -
Spread salted butter on both sides of each bread slice to keep it from going soggy and to add some richness.
05 -
Place a layer of chicken filling on one bread slice, cover it with another slice, and gently press it all together.
06 -
If you want, trim off the crusts, then cut each sandwich in half. Serve them up right away or pop them in the fridge for 15–30 minutes to firm up the filling and make slicing a breeze.