What to play vs. 1. d4 when Sicilian is my favorite defense? I've been playing chess since my childhood however just recently got into chess very seriously and my online balance was approx. 90-60 out of 150 games and then I lost 25 games due to a broken phone. Now I'm rated 1323 and my balance is 118-96 rising drastically from 1116 a month ago. Currently I'm playing 20 games and winning in about 16 of them. I have been playing very well since learning new openings. So I would say I'm experienced online when I have been challenging people and mostly I am the white player which I do play very well as against >1400 using Stonewall as white and generally winning 9 out of 10 games. Recently I have been using Kopec system vs Sicilian defence players and wrecking my opponents. But I have been playing as black more often now for overall game development and started using Sicilian def. but found that playing against 1.d4 gives me serious trouble and confusion of how I should play it. For example:

[FEN ""]
1. d4 c5 2. dxc5 


leaves me in an inferior pawn position and enemy queen staring me down 

I am more a tactician and I set up position rather than setting up traps or use an exchange of pieces to gain center board position until I have better position/castle and I am up on pawns/pieces and then gg.
You can play the Stonewall defence with black as well, as quid suggested. You can start with a Dutch and get the familiar structure (just an example):

[FEN ""]
1. d4 f5 2. c4 e6 3. g3 Nf6 4. Bg2 d5. Nf3 c6




Or you can play as you have shown and don't have to worry about dxc5 (it actually isn't such a good move):

[FEN ""]
1. d4 c5 2. dxc5?! e6 3. Nc3 (3. b4? a5 4. c3?? axb4 5. cxb4 Qf6-+) Bxc5=


If this variation was your only problem, it should be solved now... :-)

If you don't mind playing Benoni or the Benko gambit I would stick with this variation.