The technique for finding the supreme source on something that's not too biased, very in-depth but just biased enough to support your side of a debate lies in how you use your search engine.
This is where the reason people use DuckDuckGo instead of Google can kind of backfire. Google learns your biases and general topics of interest (which you can opt-out of here:
Even with them off, you enable Google to give you more tailored results for you via your Internet History on Chrome, if you use that. Whatever paranoid and legitimate reasons you have to hate this, just for a second understand that everything about the search engine is designed to learn from your previous searches (such as the one you just did one second ago and potentially disliked the links of) to contrast it with your new similar search, combine that with your general location from your IP address, notice the wording patterns you use and match the very way you write to sources in an abstract way that understand how you're prioritising keywords.
You will find that if you dislike the sources that show up in your first search, refining it isn't too hard as you need to 'work with' the search engine you have. If it's DuckDuckGo, spell it all out, every detail that's annoying you for being lacked in sources that show up, if it's Google simply search more adding 2-or-more keywords each 're-search'.
Then, skim read sources to see their stance, conclusions and commit confirmation bias in a controlled manner (did you like that 'con' alliteration there?). Stick with the ones that somewhat support your stance, be careful if you're cherry picking middleground or oppositional sources to your stance and your opponent is left with nearly nothing to use against you.
Of course things like .gov, .edu and .org are generally more reliable than .com but a blog post by a dedicated online journalist is nothing to be ashamed of using.