Touching counts
Fingers on a new food are useful. They are finding out if it is wet, soft, or surprising.
Mess is part of the introduction
Hand them a spoon if they want one, and also let fingers be allowed. Mess on a new food is part of the introduction.
A squash, a smear, a poke. That is learning the food with a hand. Wipe at the end, not at every touch.
The familiar food stays easy
They may touch the new food and eat the familiar one. Both can happen in the same meal.
If the mess is only on the new food, leave that food there. Do not clear the whole plate because a hand got involved.
When touching becomes throwing
A poke is not a throw. If the food starts flying, take that piece away and end the game. The familiar food can stay if they are still eating.
Throwing every meal is a reason to shorten the meal, not to ban hands.
A sentence you can say
“You can touch it.”