A while back, as in several years ago, I posted my House Pattern for quickly-knitted fingerless mitts, aka Wrapid Wristers. In that post, I alluded to a mitten variation. Here is the more formal pattern for those mittens.
Since k1p1 ribbing is very stretchy, these mittens need no shaping. They fit a variety of hand sizes. If you need them to be a bit bigger or smaller, you can either change your gauge or you can add/subtract a few stitches (a multiple of 2 stitches, so the ribbing pattern remains the same).
I'm not sure about yarn requirements. 100g ought to be about right, give or take a bit. I often use leftovers and oddballs and bits of handspun, combining 2 strands to get a nice thick mitten fabric.
Wribbits (easy ribbed mittens)
Cast on 24 stitches. Join, and *k1, p1* for approximately 5 to 5.5". (this is a 1x1 ribbing pattern) This gets you to the web of the thumb. So, if you like longer cuffs for your mittens or you have long hands, knit for longer than 5.5"
On the next round, put 3 stitches on a holder. I usually put stitches #13-15 on the holder. These stitches are a (k,p,k). However, you can put any 3 stitches on a holder. Cast on 3 stitches over the gap and continue in the k1p1 rib for another 5" or so, or however long your hand is.
Now it is time for a quick decrease to finish the mitten tops. On each of the next two rounds, *SSK* around. This gets you down to 6 stitches. Cut the yarn, run it through the stitches, pull it snug and finish off. (You are doing SSK instead of K2tog to keep the knit stitches on top of the purl stitches for the first round of decreases. If you have a strong preference for the k2tog decrease, then knit the first stitch of that first round before starting all the k2tog decreases. That first stitch will end up getting incorporated into the last decrease of the round.)
For the thumb, pick up stitches from the 3-stitch cast-on, the 3 stitches on the holder, plus one stitch on each side at the gap. Keep it in the k1p1 rib pattern. (the stitches at the gap help you stay in pattern) You should have 8 stitches on your needle. Do *k1,p1* rib until the thumb is about 2.5-3" long, or however long your thumb is. On the next round, *SSK*. This leaves you with 4 stitches. Finish them off as above.
Make another mitten for your other hand. Both mittens are the same and can be worn on either hand. The ribbing stretches and clings as necessary to go around the curves of your wrist and your palm. If you are careful about how you hide the yarn ends, these mittens are also reversible, should you care.