The description of Santa in this puzzle's flavor text is supposed to evoke the famous description of his laugh in "A Visit from St. Nicholas" by Clement Moore:
He had a broad face and a round little belly,
That shook when he laughed, like a bowl full of jelly.
The colors are official colors for 7 flavors of Jelly Belly jellybeans (as of 1997; they changed in 2002 - see the old flavors here), and the numbers are indexes into the official names of those flavors:
The indicated letters spell the answer, EAGERLY.