Whisk together dry ingredients in a large bowl; add the buttermilk and egg and whisk until smooth. Let stand 5 minutes (batter will thicken). If it's too thick to pour easily, thin with more buttermilk.
Cook the sausages and let them cool, then stick them on the wooden sticks. In a wide, medium-large pot (it will need to accommodate the sticks too), heat a few inches of canola oil until hot but not smoking. Dip each sausage into the batter, holding it by the stick and rolling it around until well coated - dip into the oil and cook, turning as necessary, for a minute or until deep golden. Cook only two or three at a time, without crowding the pot, which could cause corn dog collisions and cause your oil to cool down.
Drain on paper towels and serve immediately, with maple syrup.