I'll give you the ingredients first, and then talk about microwaves and cooking times:
1 cup white sugar
1/2 cup light corn syrup (like Karo)
1 cup salted peanuts
1 teaspoon butter
1 teaspoon vanilla extract
2 level teaspoons baking soda

Prepare everything you need before you start the microwave. Spray a cookie sheet with cooking spray (see note below), measure out the nuts, butter, vanilla and baking soda, set it all within arms reach.

Basic instructions are: In a 2 & 1/2 quart microwave safe bowl, mix the sugar and corn syrup until all of the sugar is moist. Microwave on high for xxx minutes, remove from microwave and quickly stir in the peanuts. Microwave on high for xxx minutes, remove and stir in butter and vanilla. Microwave on high for xxx minutes and remove for the last time. Stir in the baking soda. It will foam up; try and distribute the baking soda with as few strokes as possible since every stroke (after it foams up) will reduce the number of air bubbles (air bubbles = good candy). Pour the hot candy out onto a prepared cookie sheet and TILT the cookie sheet to help the hot candy to "move" (don't use a utensil here...just tilt the pan). Be careful, this candy (and the pan you tilt) are going to be hotter than blazes, so be careful. When candy is at room temperature (it's going to take a while), break into pieces.

The following directions were written for a 900 watt microwave:
Microwave on high 4 minutes, add peanuts, microwave on high for 3 & 1/2 minutes, stir in butter and vanilla microwave 1 & 1/2 minutes. Remove and add baking soda.

The following directions were written for a 1100 watt microwave"
Microwave on high for 3 minutes 45 seconds, add nuts and microwave for 2 minutes and 45 seconds, add vanilla and butter and microwave for 30 seconds. Remove and add baking soda.

The following directions are for a 1500 watt microwave. This is the only one I can vouch for, since my microwave is 1500 watts. Three minutes on high, add peanuts, microwave on high 3 more minutes, add butter and vanilla and microwave on high 1 minute, remove and stir in baking soda.

NOTE: The original recipe said to grease a cookie sheet. I've done that with other brittle recipes, and it gives the back side of your candy a greasy feel. If you pour the hot candy onto parchment paper lined cookie sheet, it will pop right off of the paper when it cools.

NOTE: It is good (but not necessary) to warm up the peanuts a little before you add them.

NOTE: Don't even TRY to wash the bowl and utensils by hand, just throw them in the dishwasher and they will come out clean.

NOTE: The first time you make this peanut brittle, keep an eye on the candy (as it cooks). You are going for a nice golden color, not a golden brown.

NOTE: Store finished candy in an air tight container (or it will get sticky).

Such an easy recipe! Looks delicious! I'm getting a new microwave soon, then hopefully I'll know the wattage!

My husband LOVES peanut brittle and rarely make it for him because it's such a pain. Your recipe looks like one I can handle though!

My husband loves peanut brittle. This will kill his banana diet!!!

My mom had a microwave peanut brittle recipe that came with her very first (and only!) microwave. She was hooked because it is so simple and it was her favorite. As you said, it can be tricky to figure out the wattage of your microwave. I looked all over mine for something that said (although I wasn't able to look on the back since it is built-in), but I took the brand and model and was able to find it online and was able to see the wattage that way. :)

Looks like its going to take me longer to figure out my microwave than to make this! Thanks for sharing it looks yummy & definitely easy!
~ingrid

I LOVE peanut brittle, I had no idea you could do it in your microwave. I can't wait to try this!

I love peanut brittle. This looks so good! Love that it can be made in the microwave!! I'll certainly have to give this a try. Coleen, you have such great recipes.

I love microwave recipes like this, they're so easy!! Your notes are helpful as always, I bet the peanuts are better warmed up! This is a keeper recipe for sure!

What a great recipe for peanut brittle!! I never thought of making this in the microwave - a great idea!

My aunt makes this version for the holidays and it's a keeper!