Brownies from scratch...in France

Hello all...or shall I say bonjour?! That's right, I'm in beautiful, wonderful France, staying here for a few weeks to help out my friend with some babysitting.  We (my son and I) are lucky enough to have a kitchen to use, so you know I would end up cooking at least a few things here, right?  Only thing is, baking here is a bit different.  I hadn't realized just how different until last year when I was here and wanted to make an American-style cookie bar for my friend.  When I went to buy ingredients, I found all that I needed except one: brown sugar.  I'd already read about the different flours and stuff like that, had converted the recipe to metric, but had not counted on not finding this ingredient, one so common in the states.  Anyhow, long story short, the cookie bars turned out great and I decided next time I'd bring some brown sugar along with me.
My friend's birthday was a few days ago and I wanted to make her a treat as a present.  I don't have any cookie sheets in this kitchen, so a cake or bar cookie would have to be it.  Brownies, yes, I thought, I bet I could do that!  At home in the states, I will admit I do not make brownies from scratch, as I find the Ghirardelli Triple Chocolate mix ones are fantastic (and super fast/easy), so this was slightly new territory.  I found ingredients that would work, but forgot one thing: there are no measuring cups nor scale in this kitchen.  Oops.  I don't have a car and don't really want to buy a scale just for a couple of uses here, so I went MacGyver: used a drinking glass that looked to me like it was approximately 1 cup.  And guess what?  The brownies turned out pretty good :) When I return to the states, I plan to try the recipe again and compare.

Link to original recipe:  https://sugarspunrun.com/brownies-from-scratch/

Ingredients (that I used in France):

175g (12 T.) unsalted butter, cut in small chunks
100g bar of dark chocolate (70% cacao)
*1/2 c. unsweetened cocoa powder
*3/4 c. granulated sugar (sucre en poudre)
*3/4 c. (packed) light brown sugar (from the states)
2 large eggs plus 1 egg yolk
*1 tsp. vanilla extract
*1/2 tsp. salt
*1 c. flour (type 55)
100g bar of dark chocolate, broken into "chips" (chocolate chips are quite pricey here, so this is the better option :))

(*=approximation, no idea if accurately measured here)

Instructions:

1. Heat oven to 175°C (350°F) and prepare a baking dish/pan--either line with parchment or grease sides and bottom (I did the latter).  It's supposed be a 9"x9" or 13"x9", but all I have here is an oval dish of unknown measurements (it looked about the right size :))

2. Combine butter and 100g of dark chocolate in a large, microwave-safe bowl (mine wasn't so large, as again, I'm limited on equipment here).

3. Microwave at 700W for 30 seconds.  Stir, then microwave for 15-20 seconds and stir again, repeating process until a smooth melted mixture is obtained.

4. Stir in cocoa powder.

5. Stir in sugars until completely combined.

6. Stir in vanilla extract.

7. Sprinkle salt over batter and stir to combine.

8. Add flour, stirring until completely combined.

9. Stir in chocolate "chips". (yep, I had to change bowls)

10. Spread into prepared baking dish and transfer to oven.

11. Bake until brownies jiggle only slightly in middle when you gently move dish back and forth.  For the dish I used here, this was 24 minutes.

12. Cool, cut up, and enjoy!