heat a skillet over med-high heat. lightly spray with cooking spray. Add sausage links to pan and brown on all sides. Approximately 4 minutes total.
while sausage is browning start slicing the peppers and onions.
over medium heat, heat olive oil in a saute pan for about 30 seconds. add minced garlic for another 30 seconds. Add peppers and onions and saute for about 4 minutes. (might have to do in 2 batches depending on your saute pan size). add salt and pepper to taste (I did about 1/8 tsp each)
add sausage to crock-pot. top with peppers and onions.
set crock-pot to low for 4 hours. 2 hours in, take sausage out and let it rest for 10 minutes on a cutting board or cooling rack.
slice sausage and add back to crock-pot. Stir.
serve on a bun, solo or with a cornbread side. top with sweet and spicy mustard. Enjoy!