However, we can get close with a few options, depending on what aspect of the phrase you want to focus on:
* "Stir" is a homonym for "to mix" but it doesn't include the utensil.
* "Spoon" itself can be used as a verb meaning "to scoop up or take food with a spoon," but it doesn't directly convey the mixing action.
For a more creative approach:
* You could use a phrase like "to ladle" which is a verb for "to scoop and pour out with a ladle," which is a similar utensil to a spoon.
Ultimately, the best "homonym" would depend on the specific context and what you're trying to convey.