5-minute Molten Chocolate Lava Cake

I developed this recipe based on the popular “Microwave Chocolate Mug Cake” that makes the email rounds every year.  That recipe was actually developed by a Spanish molecular gastronomist (basically a creative food scientist/chef) and was considered a “high cuisine” dessert, to make and serve tableside at his $200-a-plate restaurant, to the amusement of his guests when they saw a microwave being wheeled out of the kitchen toward their table.  I personally found the recipe to be missing a little something, so I added some coffee to give it depth of flavor, changed the milk to buttermilk for additional flavor, lift, and tenderness, and added a molten chocolate center.

The great thing about this recipe is that it takes less than 5 minutes from start until you’re eating it, with practically no dirty dishes.  Don’t blame me if you get addicted!!!

In a large measuring cup or small bowl, combine:

4 Tablespoons all purpose flour
4 Tablespoons sugar
2 Tablespoons cocoa powder
1 Tablespoon instant coffee
1 pinch baking soda
1 pinch salt

Stir these around with a fork until they are well mixed.  Then add:

3 Tablespoons canola oil
3 Tablespoons buttermilk
1 egg

Stir with your fork until most of the lumps are gone.  Distribute the batter into 2 glass tumbler cups (or any small, wide glass cup, ie not a juice glass) which have been sprayed with cooking spray.  Then take:

1 oz square of semisweet baking chocolate

Break it in half and place each nugget of chocolate gently on top of the cake batter in each cup.  It will begin to sink.

Place both glasses in the microwave and set the time for 2 minutes on full power.  Depending on your microwave’s power, it can take anywhere from 75 seconds to 2 minutes to cook.  Watch the glasses carefully, the batter will rise to, and possibly above, the rim.  My 1100 watt microwave bakes these cakes in 75 seconds.  My neighbor’s 900 watt microwave takes 95 seconds.  Try not to overcook the batter…you will probably not use the full 2 minutes unless you have a very small, low-powered microwave.  It is better to undercook this cake slightly than to overcook it.  After making these a few times, you’ll find that sweet spot number for your microwave.

Open the microwave door and let the cakes sit for 30 seconds to allow them to settle and the steam to rise.  Then turn them upside down onto saucers to unmold the cakes.  Cut into them and melty chocolate will ooze all over your plate!  Serve with whipped cream or ice cream, or just dust with some powdered sugar.

22 Responses to 5-minute Molten Chocolate Lava Cake

  1. I have tried to make this but instead of the center being Chocolaty the top is. Is there any way to fix this or am I do something wrong while making the cake? Also should I let the chocolate sink all the way to the bottom or put it in right after I insert the chocolate? Thanks!

    • Depending on the shape of your chocolate chunk, it may sink all the way to the bottom before it gets locked into the batter and melts. Nothing wrong with that. When you cut into the cake, it still drools molten chocolate, right? It’s normal to have a dot of the melted chocolate at the top of the cake once you invert it. But if the whole top is a layer of melted chocolate and there’s NONE in the center, you could have a slow microwave, or you could try a different cooking glass…

      • When I cut into the cake nothing oozes out since all the chocolate got stuck on the bottom. I make the cake in glass cooking cups. Should I instead try something like a coffee mug or microwave safe plastic of some kind? Could it also be because I’m using semi sweet chocolate chips(like on masterchef) instead of squares? If that is the problem should I maybe melt the chocolate and then freeze it and break it into large chunks? By the way the recepie is super good with the little bit of coffee in it. Thanks!

        • You’re just cooking it too long! Cook it until the batter rises just above the top of the cups (assuming you’re using small tumbler type cups) and then give it 5 seconds more and stop. If that’s still too long, keep shortening the time you cook it. Once you find the sweet spot, write it down and you’ll always know EXACTLY how long to cook the cakes!

  2. I can’t wait to make this! I’ll let you know how it goes!

  3. Lam Thi Minh Trang

    what’s about your glasses’ size? I mean the diameter of the ramenki cup :)

    Thank you very much :)

  4. Lam Thi Minh Trang

    oh I forgot. Could I change Canola oil to butter? I cannot manage to find one in my place :(

  5. Hi, Ben! You just saved my day! My girlfriend’s gonna love this. She loves chocolates and cakes.

    I was desperately looking for something for our anniversary and then Wikipedia brought me to your website.Wow you’re so inspiring! Hugs and kudos all the way from Hong Kong!

    In return, when you have time, check out
    ^ this one is my favourite Chinese dessert!

    Not sure if you have any interests in Asian stuff, but I guess it won’t hurt to take a look and see if it can inspire you.


    • Thanks so much for your comment! I love Hong Kong, I’ve been there twice. And I’m ALL about unique recipes from other cultures, that is what drives my culinary creativity. So I’ll definitely check out Douhua and Tangyuan!

  6. Thanks Ben! I made this cake when I was desperately craving a rich delectable chocolate dessert and temporarily had no stove top or oven! Only took 60 seconds in the microwave, and it did not disappoint :) You’re a genius!

  7. My 7 year old loves you! His fav dessert is only seconds away from being created now….and I have a monster on my hand…this is so easy he did almost all of it (I did the egg)! lol

  8. I finally got around to trying this recipe, even though I only had some white chocolate on hand. Holy Cow! This was awesome!

  9. Where can i buy the white cups? please reply:)

    • White cups? Do you mean the clear glass tumblers I use? Anywhere…they are not specific. They do not have to be a certain size. Just glass…and microwave safe. I’m sure whatever you have in your cabinet is fine!

  10. I just made this and my husband, who doesn’t like cake, actually liked it. I used a slice of one of those dark chocolate oranges, which was ok. Next time I’ll use a really dark chocolate. I cooked it in two wide mouth Mason jars, which were just right. Overcooked it a bit, but I’ll fiddle with it until I get it right.


  11. What’s the name of the gastronomist who inspired this?

    • Sumy, lots of folks attribute it to Ferran Adria, chef of the famed El Bulli (ie, the best restaurant in history). But I’m not sure if he’s the first person to come up with it.

  12. Just tried it. I had to go longer than 2 minutes because my max output is 700 watts. It still oozed on the outside, but tasted great.