Increasing Toast Level on my Medium Toast Cubes

Starting a Oaked Bourbon RIS tomorrow and all I have is Hungarian Medium Toast cubes. I want to get something soaking in bourbon ASAP.

Went to LHBS to find Heavy Toast cause that's what I want to use, but none there.

Can I just toast my medium toast cubes more in the oven? I know I could toast my own, but I am wondering if starting with something that was already toasted, and then putting it back in to toast more would be problematic in any way.

Also, if so, what temp and how long?

I can't find a reasonable place to order some. Nothing on Ebay, Nothing on Amazon, and none of the online retailers have realistic shipping rates on 3 oz of cubes. I just put in a big order and wish I would have thought of it then.

I've never tried toasting my own or increasing the toast level, so I have no experience with times and temp. Doing a google search I saw a couple posts on a distillers forum indicating 400F for anywhere from 2-3 hours for untoasted oak.
Here's an HBT thread on the subject, https://www.homebrewtalk.com/showthread.php?t=32048
And another, https://www.homebrewtalk.com/showthread.php?t=287013
Also found this write-up which indicates it's a bit of an art-form, so they didn't recommend doing it at home, http://www.eckraus.com/blog/making-your-own-toasted-oak


Maybe let people know where you're at. There might be a local brewer that has some.

Scott just toasted his own...check out his blog: http://www.bertusbrewery.com/

http://www.homebrewfinds.com/2015/03/guest-post-toasting-your-own-wood-chips-by-matt-del-fiacco.html

I did a Surly Smoke clone, toasted my own oak chips, 400 degrees until dark enough. Came out with great vanilla flavors. Now I always toast my own.

But I always buy lightly toasted wine chips, I don't want to have to hold onto wood for years to be sure it is dry enough. Not terribly expensive.

Thanks for all the responses. In this case I just ended up putting in another big online order and including some American heavy toast cubes. The ones I got are fire toasted I guess, so I am happy with them.