This orange-scented upside-down cake does it all, environmentally speaking. It prevents food waste by upcycling the contents of the nearly empty bags of nuts in your freezer that you refuse to throw out; and it’s plant-based — two carbon-saving moves. It also calls not just for all-purpose flour but for a portion of some other flour, too (use whatever’s in your pantry!), since branching out from the world’s most widely grown wheat is good for climate resilience. Inspired by Alex Testere’s mixed seed upside-down cake, this sustain-ified version pairs a cake perfumed with orange zest with a seedy, nutty olive oil caramel. Raw or roasted seeds and nuts like pecans, walnuts, almonds, sunflower seeds, and poppyseeds are all good places to start, but let what’s on hand be a guide. (Though a word to the wise: If you have fennel seeds, use them! Your kitchen will smell like a holiday in Italy.)