If you are getting juice in the mouth, you might have overfilled. Don't quite remember how many drops you should put into the attie for 306's. For the dual coil atomizers I use, the hold allot of juice, i put about 8 drops in, let it sit for 30 seconds then put in another 6 drops. When it is empty tasting I put in 6 more drops. For most 510 atomizers its usually 3 drops from dry, 30 seconds then 2-3 drops more.
Does the atomizer vape really sluggish when you get juice in the mouth? What voltage are you vaping, this might effect it as well.
Another suggestion, the snickerdoodle is heavy in cinnamon, that flavor is really hard to remove from anything. Vodka will remove the flavor most times. I would get a seperate attie for the flavor or throw it into a cartomizer. I have dripped snickerdoodle in an attie and it never really vaped out. I had to actually soak it in alcohaul or boil in water to remove the flavor. Some people get some vg or pg non flavored and use that to vape the flavor out. YOu could just put another flavor in and within 2-3 drip periods, the bulk of the flavor should be gone.
Another thing you might want to check out is a drip shield if you are not using a 306.