The thread title says "favorites" instead of "best" of 2019, which is a good thing, because I didn't take any magazine quality photos in 2019. I'll start with the most technically challenging photo I took last year, a family portrait with me holding the infrared remote, with on-camera flash bounced off a wall (instead of the ceiling because my tripod is too shot, so I placed it in the kitchen and we stood in the family room which is about 18 inches lower (both ceiling and floor). I couldn't do anything about the busy background and if I used a wider aperture than f4, some of our faces were out of focus. Since my daughter lives 2000 kilometres away and my son lives 3000 kilometres away, it was a special occasion to have the four of us together.
Then my favorite flower picture of 2019, a Brugmansia that only flowers in November, when it is much too harsh outdoors, so in September we bring it inside, let all leaves shrivel up and fall off and then one or two very fragrant blooms magically appear, followed by a playing dead period of 4-5 months.
Finally, I don't normally do B&W conversions, but I purposely went out one evening to look for a suitable photo to submit for an urban B&W challenge. No matter what I do in post-processing the full colour version, it turns out much worse.