This step is optional. I like to brown off the chicken bones before I use them. The browning of the bones allows the fat on the bones to rendered off in a pan. I collect this fat for roasting vegetables and other recipes
The vegetables in this broth don't have to be finely cut. The onion, garlic and ginger and lemon can be halved. I cut the carrots and leeks into chunks. Also, note that I often only use the green bits of the leek for making broth.
Arrange the vegetables, herbs and chicken bones in a large stockpot. I usually cook mine in 4.5-quart pot pan. Arrange the vegetables and chicken bones in the pot, and fill up with water. Then bring up to a boil.
Once the water in the pot is boiling, I turn down the heat to a simmer, and then I start the clock. I'll usually let the broth simmer for about an hour after it comes to a boil. Let it cool down completely before attempting to strain out the liquid.
If you have a bit of fat floating on top, this can be captured by putting the broth in the freeze let fat solidify. Then the solid fat can be picked off the broth. I usually don't have this issue since I render the fat off before making the broth