Rinse the chicken and remove the "bits" from the cavity. Pat dry with paper towels
In a small bowl, whisk together all of the seasonings (salt, pepper, paprika, onion powder, garlic powder, thyme, herbs de Provence)
Rub the spice mixture all over the chicken, and sprinkle some into the cavity
Pack the onion and garlic into the cavity.
Optional - squeeze the lemon juice over the chicken.
Roll up some balls of aluminum foil and put in the bottom of the slow cooker.
Place the chicken on top of the foil balls, breast side down.
Chicken is cooked when a thermometer inserted in the thickest part of the breast reads 165 degrees F
Cover and cook on high for 3-4 hours, or on low for 7-8.
Remove chicken from slow cooker, and slice.