1. Mix salt, pepper, and ingredients for seasoning paste, if you are using it (with seasoning paste, use a large bowl). For chicken without seasoning paste, rub all over with oil, then with salt and pepper, putting a little inside too. For chicken with seasoning paste, slide 2 fingers between breast skin and meat to make pockets. Turn chicken over and loosen thigh skin the same way. Put chicken in bowl with seasonings; smear some in pockets, inside cavity, and all over outside. Set chicken breast-up on a V-shaped rack in a 12- by 17-in. roasting pan; tuck wing tips under if you like.
2. Let stand at room temperature 30 minutes. Meanwhile, preheat oven to 475° for a 3- to 3 1/2-lb. chicken, 450° for a 3 3/4- to 4 1/2-lb. bird, or 400° (for any size chicken) if using a seasoning paste (to prevent scorching).
3. Roast until an instant-read thermometer inserted horizontally through thickest part of breast reaches 160°, 30 to 35 minutes for a smaller plain bird, 45 to 50 minutes for a larger plain one, or 1 to 1 1/4 hours with a seasoning paste; after 30 minutes, begin checking chicken occasionally, and if any areas are getting dark, tent them with foil. Let chicken stand in a warm place 10 minutes; transfer to a platter.
*To find small (uncooked) chickens, try markets that roast rotisserie birds (which are small) on-site.
Note: Nutritional analysis is per serving plain chicken.