Lager-ale experiment

Had our first hard frost yesterday, so I started thinking about a lager. Then I thought about making another ale. Then, how about making a 10 gallon batch of wort and do two ferments? A lager AND an ale.

Now the tough part, what sort of a recipe would be best? It will probably be a partial involving 8.75 pounds of Maris Otter LME (it's been in the freezer for months). I'll have to make a LHBS run for the lager yeast, so the other ingredients are open. I tend to the dark side, but I've never made a black lager.

Anyone try this before?

Any suggestions?

Pick up some special carafa and do a shwartz / alt combo. That would fit the bill I should think.

Might work. I'm also wondering what Roque Mocha Porter would taste like lagered. I suspect any lager characteristics would be lost with that much caramel (1.5 lbs).

Special carafa might be tough to find around here.

I would say limit the roasted malts but any crystal is game, even the schwartz is limited in this respect. I would go for anything in the amber range. Since you mentioned Maris Otter, I have wondered how a British malt would do for a lager. I prefer to purchase bulk German base malt as I can make a fine ale along with my lagers but been wondering the reverse.