Any warm desert recommendations ? ?

Mug cakes are always good for single servings if you don't want to bother baking a lot. You can also make fruit cobblers, dump cakes (cake mix, canned fruit filling, you're done), oat crisps, pies...whatever you want. Cookies and brownies are good the first day, but not really great the second when you go to heat them up. All the desserts I mentioned are either enjoyed that day, or you can heat them up again. 

Look up recipes online. Crisps are really easy to make. I make a really good apple, pear, and cranberry crisp. And I personally prefer to make mug cakes without eggs, but that's just me. There are a ton of recipes online for every kind og mug cake, pie, cookie, and pudding imaginable. 

-Pumpkin pie

-Hot chocolate with marshmallows 

Slice an apple and bake in microwave.

crepes with nutella and ice cream

That's up to you. We don't know what you like, what's available where you are, or why cooler weather would have any impact on what you choose to eat for "dessert" (desert is dry/barren land where few things grow).  Warm desserts would be cookies, cake, brownies right out of the oven (or popped in the microwave a few seconds). Plenty of people still eat ice cream and other cold/frozen treats even in the winter time.

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