Season with zesty Cajun seasoning, pepper, and blackening seasoning. Roll frog legs in flour and set aside.
In a large black skillet bring butter and grape seed oil up to high (don't burn the butter, it will brown when burning) not much oil and butter, just about half an inch or so. When oil and butter starts sizzling, put frog legs in and brown on each side; should be about half way up on frogs, just enough to brown. If butter gets low, throw another half stick in.
Set browned frog legs to side, now, with what's left in the pan (which is the BEST of what's left), add white wine, garlic (whole pods, peeled), mushrooms and cook for a few minutes.
Add all of your frog legs back in on top of this, put lid on and cook in oven for about 30 minutes on 300. According to how big legs are, these tonight were HUGE so they didn't cook fully in browning process. If they are small then cook less. Meat will be falling off the bone, you will know its done, believe me!
You can't mess frog legs up, they are the best! Go find a ditch, catch some frogs and get to cookin'!!