So, in an attempt to remedy that situation, I leaped headfirst into my first batch of cucumber bread. I made it sound awful, but it wasn't. It just wasn't quite perfect for going with the frosting; I think leaving out the cinnamon would have let that fresh cucumber taste really shine with the peanut and lime as it should have. So, here's the recipe I created that truly is worth every last calorie, and it need not be limited to cucumber bread. I daresay this would dress up any vegetable cake masquerading as a "bread:" cucumber, zucchini, pumpkin, carrot. I believe that it would even make a delightful topping for an actual cake, perhaps a white or strawberry flavoured one. Well, definitely a white one, anyway. After refrigerating, its nature is akin to a savory spread, and is a little dab of heaven on earth. You can always return it to its previous spreadable frosting state by whipping it with your mixer and maybe a dab of milk. Here it is:
Peanut Lime Frosting
*I didn't measure exactly as I made this, but went rather by taste. I suggest you do the same by conservatively adding ingredients, then adding a little more of whatever you think it needs.
1/2 cup butter (1 stick), softened
1/2 cup peanut butter
1/4 cup coconut milk
1 tsp sesame oil
zest and juice of 1 medium to large lime
1 tsp dark soy sauce* (yup, you read right)
1/4 tsp salt
3-4 cups powdered sugar
Combine butter and peanut butter in a medium bowl and beat until combined and fluffy. Add coconut milk, oil, lime juice and zest, soy sauce, and salt, and mix well. Add powdered sugar 1 cup at a time until desired consistency is reached (I used close to 4 cups.) Use immediately, or refrigerate and rewhip to soften when needed. It's quite an amazing spread when served chilled and just soft enough to smear over a crust of bread.
*I've not substituted in regular soy sauce, so I can't testify to the viability of a substitution here. You could always leave it out if you're too afraid (you chicken!)