I put a light brush of yellow mustard all over the chicken, whole or breast, then I splash a little Worcestershire sauce on then I sprinkle on some Tony's seasoning, garlic salt, ground pepper and a pinch of dry parsley. Sometimes I use some Mrs. Dash too.
Adding the layer of mustard makes a great difference but you don't taste it.
When doing a whole chicken I put it in a roasting bag along with some potatoes and onion and a little wine.

Buying the whole roasted chicken from the deli is cheaper than buying a raw chicken and having to cook it. They offer a multitude of seasoning depending on your tastes.

My top three favorites:

-Rosemary and sea salt
-Cajun seasoning
-Scarbourough Fair-Parsley, sage, rosemary, and thyme

Higher temps (like 385), whole spatchcocked chicken, so it can cook quickly (around 40-45 minutes), and it stays moist. I've never done just the breasts? That's probably good too, but I don't have temps/time for pieces. Sorry!

That mustard idea sounds fantastic to me.

As far as seasonings go, you can't go wrong with a brush of oil, then a sprinkle of kosher salt and black pepper.

If I bake/roast (I don't know the difference, either) a whole chicken I usually mimic the way I had them in Spain way back in the glorious 80s.

Crush several garlic cloves; mix them into a thin paste with olive oil, a little squeeze of lemon juice, and course salt. Sometimes I add black pepper, too. I usually make this mixture an hour or more before baking so the flavors can meld.

Rinse and pat dry the bird. ( I try to do this the night before so it can drain and dry over paper towels overnight. I don't like cooking "wet" chickens.)

Gently wiggle your fingers under the skin to loosen it from the front, back, and thigh areas.

Smear the garlic/oil/lemon/salt mixture on the flesh under the skin. Coat it as completely as possible. Thin slices of lemon can be put under the skin on the breast area if you like. (If I do this I usually don't add the lemon juice to the oil mixture.)

If any of the oil mixture is left over, smear it in the cavity. Add a couple of thick slices of lemon and/or a slice of onion in the cavity.

Bake until done! Delicious.

I like lemon with chicken so I usually squeeze some fresh lemon juice over the bird right before serving, or once plated. I've been known to nix the lemon and use crushed Rosemary in its place.

I brush chicken breasts with a Honey Mustard salad dressing before going into the oven or on the grill.

I cook chicken breasts in a pan with a little olive oil over low heat, turning once. Salt, garlic, lemon juice. No breading. No deep fat frying. No hot oven. We haven't owned a BBQ grill in decades.

I bake whole chickens with a little salt and pepper, quartered onion, stalk or two of celery and a big bay leaf. Put a little of this inside the bird too. It's very flavorful. Leftovers go great in a variety of dishes.

To answer your second question, Pammyfay, the answer at the link will likely be sufficient.

Here is a link that might be useful: Difference Between Baking or Roasting

I broil breasts after putting Its a Dilly on one side and Punch Yo' Daddy on the other. Broil on low, turning once.

We love skinless boneless breasts rolled in a mixture of melted butter, dijon, garlic and a splash of worcesterhire sauce, then rolled in bread crumbs. Sometimes I add parmesan to the bread crumbs. Baked at 375. Juicy and tender.

I use lemon pepper on turkey, should work on chicken too.

Jasdip, I like your method. How long do you bake the skinless chic. breasts? Don't want to dry them out, but want them thoroughly cooked.

Shel, generally about 45 minutes at 375.
Patti43 who doesn't post much anymore, loved these!!!! She and Harry ate them regularly, and she always called them Jasdip's Breasts, whenever he would ask what was for dinner. LOL

I think we should all try Jasdip's breasts LOL!!!
That is funny. But it does indeed sound delish. I do some thing similar generally I use Panko crumbs.
You can always use one of those thin digital meat thermometers to check for doneness. My old one left a huge hole in the meat so I got a very thin one with a digital read out and it is much easier.
I am pretty sure I got it at Bed Bath and Beyond on their wall of everything you may ever need for the kitchen. I love visiting that wall!

I made jasdip's chicken last night for dinner. Hubby and I enjoyed it. Thanks for the recipe.

Y'all are making me blush, and they're not even Rob's breasts. That sounds so funny! Jasdip, I'll have to try those soon. But I'm calling it somethinge else. Dijon and Worchestershire chicken?