The closest spread to peanut butter I've found in terms of flavor and texture is sunflower seed butter. It's also relatively easy to find; I've seen it in large chain grocery stores right next to the peanut butter.
A curmudgeon with years of practice. The bubbles in boiling water are steam or vaporized water. The bubbles initially do not reach the surface of the billing fluid as the colder water away from the hot bottom cools the steam turning it back to liquid. WHen all the water is at 100oC the bubbles reach the top.
Boiling Water in the Microwave. 1  1. Put the water in a microwave-safe cup or bowl. If you can't find a dish labeled microwave safe, choose glass or ceramic cookware that does not have any metallic paint. 2  2. Add a microwave-safe object to the water. This also helps the water bubble. 3  3. Put the water in the microwave.