L'chatchila: Do not bake separate pans—whether uncovered or not—of dairy food and meat food in the oven at the same time.
Reason The food might spill over.
B'di'avad, you may cook pans of dairy food and meat food at the same time in one oven if both are:

• Not touching,
• Covered, AND
• Non-liquid; i.e., either:
  • Solid, or
  • Liquid only at the beginning or end of the cooking (but not both beginning and end).