cannabutter in the oven?

Not only is it possible, but it is preferred The stove top is just easier for most folks which is why it's more common, but it leaves you more room to have a mishap, having less control over your heat source (almost every stove top burner's 'low' setting, is still too high to have such close contact with the material, while processing). This is why people use double boilers on the stove-top, to create an indirect form of contact between the heat source, and the canna. In the oven, you can set it at a specific and much lower temperature, and so long as your oven is functioning properly you can 'set it and forget it' until it's time for a stir.

This link will help you, particularly with your interest in using the oven. You'll definitely want to read more about decarbing, sealing your containers during processing, and why certain steps are recommended and necessary:

Photo Tutorial: Highly Activated Bioavailable Canna & Hash Oil, Edibles, Drinkables and more...









These recipes and more are contained in the link above, along with a detailed tutorial describing the edible-oil making process.

Have fun