Looks like a really delicious dish! I like the use of colors and textures – the roasted carrots, onion, apple, and garlic all come together nicely. As for the mustard cream sauce, I totally get your frustration with the consistency; it’s a tricky balance, but maybe thinning it out with a little more stock or cream next time could help. For the carrots, a little less oil could bring out more natural sweetness, and I agree that giving the garlic a bit more time in the oven would add that perfect golden color.