Since you have to do two of them, I believe mittens should be quick. And these bulky mittens are just that! I’ve used two patterns for these in the past:

• Quick Bulky Mitten by Aimee Pelletier
  • This pattern calls for size US 11 needles, and is my preferred pattern.
• Lightning Fast Mittens by Hill Vintage and Knits
  • This pattern calls for size US 13 needles.