I usually keep a Clif bar or a power bar in the saddlebag right next to the spare tube and tire irons.
I put a fresh energy bar in the bike saddlebag once every several months. Try doing that with a banana or PB&J sandwich.
The flavor doesn't really matter as the energy bar is In Case Of Emergency.
But the Apricot Clif bar is tasty; the oatmeal-raisin or toffee-chocolate or peanut-butter-chocolate harvest power bars are good too.

Normally during my rides I will use Hammer gel in a flask. On long/hot/hard rides I'll have Heed in the water bottle. These are easier to consume on the roll than an energy bar and don't get my fingers sticky, make litter nor require me to remove gloves. The gel flask is great that I decide exactly how much I want per serving so there is no waste. The flask lives in the fridge between rides and I'll just top it off for a few times until I dilute the gel with water to make my oatmeal with.

On rides starting rested and fueled, riding lower intensity on cool days with slower cyclists and no hills, I am fine with just water for several hours.
But on my one-hour evening training loop I am usually not fueled, not rested and am riding at threshold intensity burning mostly carbohydrates. I cannot summit the steepest hills without hammer gel "hill helper" or similar carbohydrate assist.
Even starting fueled and rested, I will fall apart within 3 hours of hard riding if I do not consume carbohydrates during the ride.