Preheat oven to 350. Spray a 9 Inch cake pan with non stick spray. Line a baking sheet with foil. Place prepared baking pan on foil lined sheet.pan.( bake cake on this foil lined pan )
In a large bowl whip egg yolks, peanut butter, sugar, sour cream and vanilla.until light and creamy about 3 to 5 minutes.
In another large bowl with dry clean beaters beat egg whites until they hold stiff peaks
Fold egg whites into yolk/sugar mixture in 3 additions. Combine gently but thoroughly being careful not to deflate. Pour into prepared pan.
Add chocolate chips to the top. Some will sink halfway while baking. Do not fold them into batter as they will just sink to the bottom when baking and stick to the pan bottom.
Bake about 30 minutes until toothpick just comes out clean. Do not overbake, but be sure center is cooked
Cool.in pan on rack 30 minutes. Run a small knife around edges to loosen. Then completely cool on rack or plate.
Garnish with whipped cream, chocolate shavings and peanuts.