Many of you asked for the recipe of the vegan chocolate brownies that were apparently based on kidney beans, apple, banana, and oats. Here we go:
I followed the recipe by "cake INVASION!". But I replaced parts of the sugar(s) with sweetener and a banana, left the chocolate frosting off and added some peanuts. Also I replaced the apple pulp by simply blending in a fresh apple. Because the banana added additional liquid, I reduced the amount of plant milk.

Process:

1. Blending oats in blender, putting them in bowl. Soaking Chia seeds in 3 table spoons water. Dissolve sweetening pills in water, Preheating oven to 175 degree celsius (two-sided heat).
2. Blending all wet ingredients together (beans, banana, apple, oat milk, chia seeds, sweet water, oil...)
3. Mixing all dry ingredients into bowl (blended oats, backing powder, sugar, vanilla sugar, cacao powder...)
4. Mixing blender content with bowl content (either in strong blender or by hand)
5. Put on baking sheet (apply oil before!) and bake for 25 minutes (testing if it is done by stick poking does not work with brownies)
6. Let cool down 
7. Eat 

• Watch "Tidying Up with Marie Kondo" on Netflix, read her book, watch the documentary by "The Minimalists", or digest the content of any other minimalism blogger (who does not interpret minimalism as an aesthetic only). A good local source in Austria might be JANAklar and partially dariadaria.
  • Then, more importantly, apply it and declutter your home category by category or room by room. 
• Fitness challenges:
  • Bronson Challenge (30 Seconds head under cold water, then maximum amount of push-ups in one minute with touching the ground with the chest, record: 128 by Charlie Bronson)
  • 100 Push-Up Training Program/Challenge
  • 30 Days of HIIT
  • Bring Sally Up Push-Up Challenge
  • Learn to translate your normal strength training plan into a bodyweight bodybuilding plan and use it (IntelligentStrength made a Solitary Bodybuilding program here)
  • Even doing 10,000 - 20,000 steps a day is an important factor in your caloric balance and has positive advantages for your mood. Maybe you can also use your staircase, if you can't leave the house at all.
• Learn multiple new dance moves
  • e.g. all these dance impressions as shown by Jennifer Lopez and Derek Hough 
  • Do one full  song of intuitive dancing a day (obviously this is also really good for your mood)
• Daily cold showers, it refreshes your mind and body and keeps you awake and "uncomfortable" in a good way. If you are only just starting try to extent it to a minute. First only your body, then also over your head
• Dietary Challenge:
  • Finally actually read "The Best Fat Loss Article on the Motherfuckin’ Internet" and educate yourself how a proper diet actually works, what macros are, what you have to prioritise to reach your goals and in general get a "No Bullshit" mindset on the topic
  • Get yourself a (precise) kitchen scale and a calorie/macro tracking app (I personally use MyFitnessPal and recommend it, but there is also FDDB, Lifesum and others). Start tracking your food. Purely at home what you eat is even more under your control than normal. Tracking correctly is a skill (people make mistakes like not tracking small amounts of very energy-dense foods like oil or forgetting to track liquid calories in drinks). Learning it is useful and can inform your intuition about your food choices long term (you will have an idea how many calories a meal roughly have even after you stop tracking, if you pay attention to the numbers). And it can give you the sense of being at least partially in control during these uncertain times. 
  • If this is too demanding, you can also set yourself easier goals like eating 500g+ of fruits and 800g+ of veggies a day
• Learn singing or at least determine your vocal range (might also help with the social distancing?)
• Learn a language, e.g. with Duolingo
• Well, obviously, read.
  • Book lists: Books required at Top US colleges, The Bill Gates Book list, Effective Altruism Books, Best Pop Science Books or check "Five Books", where experts recommend the five best books on every topic 
  • Join the World Economic Forum Book Club  or the Quillette Quarantine Book Club
  • Blogs, Newsletters... (FarnamStreet, ClearerThinking, 80,000Hours, WaitButWhy...)
  • Listen to Podcasts and Audiobooks (e.g. Podcast Addict, Audible...)
• Take care of your mental health, especially when you have depression, for example with Moodpath
• Meditate with Headspace, Insight Timer, or simply on your own
• Educate yourself on Coursera, edX, udemy, Khan Academy, Brilliant or simply on YouTube (ThreeBlueOneBrown, Vsauce...)
• Video Chat with your friends, Call your mom

Other lists about the question:

• by Spencer Greenberg
• [...]