Is there a flavor or additive that removes or hides the base “flavor” in a recipe?
Sometimes it seems that the base is too prevalent regardless of flavors added, and based on store-bought juices I’ve had, there seems to be a magic bullet that clears that base flavor out.
I read that Bitter Wizard does that, but I can’t seem to get it to work.
The only thing I’ve found that seems to accidentally do something is Flavorah Sugar Orchid, but that of course adds some of it’s own flavor.
?
Thanks
Just a suggestion you could always split the batch into 2 then adding vg/pg to each of the new batches then you can arrive at a new profile by building up the juice however you wish. Just a thought.
A magic bullet that clears the deck is more like it… that would be TPA Smooth or FA Vape Wizard both of these are typically used to tone down sharp notes within the juice but using too much devasts the flavor and whips it clean. So instead of zilch flavor why not split the batch in half and add a bit as you wish or perhaps by adding the additional pg/vg it has diluted the base flavor to your likings.
Hope this helps and sorry so wordy 
Another thought that hit me last night - what about different brands of base? I’ve been using the ones from ecigexpress and just for the heck of it I bought a bottle from Liquid Nicotine Wholesalers. I’m going to try that one when I get it and see if it tastes different.
The whole PG/VG ratio thing seems to be a piece of the recipe puzzle but I haven’t got it yet - and am not sure if it’s just a bunch of hype or if it really does make a difference in the end. Cuz if it does, that’s just one more layer of complexity that one needs to know about to make the perfect juice.
Trial and error takes SO long! 
In my experience it doesn’t make a huge difference. I started mixing max vg (so the vg usually ended up around 90% give or take), then switched to 80/20, and then recently started mixing at 70/30 for tanks but usually stick with 80/20 for RDAs. I know those aren’t vastly different ratios, but I honestly don’t notice a difference in taste. Imo vg/pg ratio is more important for what atty you’re using than for the taste. Could be a lot different if you’re talking about a much higher pg% like 50/50, but I don’t have any experience with that. Hope that’s at least somewhat helpful!
I’ve not noticed a big difference betwen suppliers , but then I’ve only used two suppliers, and I’ve heard others complain about big differences in quality.
I think the main thing is that it should be stopred correctly, by both the supplier and yourself. Heat and light both act to degrade the nicotine, so keep it in a cool, dark place, and in an amber glass bottle, ideally (my suppliers both supply in amber glass, but some don’t)
If you’re storing it long term, keep it in the freezer, It won’t freeze solid and crack the glass but it will keep much longer.
When nicotine degrades, it gets darker in colour , and devolps a bad taste. Good, fresh nic base is a very pale amber, or even white.
An update, and thanks everyone for your input.
Received Nicotine Salts from LiquidNicotineWarehouse and noticed a big difference in harshness. Right after, ordered and received 40/60 from same place and again noticed a difference, this time in the “base flavor” I was talking about.
Nothing scientific or measurable, but an observation.
Pg is very bitter the harshness you’re experiencing can very well be the Pg and not necessarily the product in and of itself. Pg is hygroscopic - this will absorb moisture and can make the batch seem to be harsh. Easy fix is to blend higher with Vg until you’ve reached a ratio that works well for you so that the harshness is toned down.
A little more complicated but wanted to also point out that testing your nicotine is of high importance especially when you talk about it seeming harsher… test your nicotine kits are available http://www.ecigexpress.com/shop/diy-e-liquid/diy-e-liquid-flavors/signature-flavors/signature-menthol-mint/nicotine-testing-kit.html they are cheap but can save your butt. I know ppl on this very forum that have nightmare stories about vendors that bottled nicotine incorrectly. Just want you to know there is always more science 
behind what we think 
You’re coming to the right place and asking questions so that is always an excellent start. I hope for your sake the nicotine is fine and that the harshness is just a preference really than anything else.
But don’t forget to test your nicotine it is one thing that is often over looked.