Just No! No lard, EVER! No cheese or onions. You ppl need help.
I'd never contemplated making gravy with sausage until attending college in Bloomington, Indiana, USA (Google it, Brits. It's lush, green, sub-tropical, & we have Internet Two). I make damn good biscuits and gravy, and here's how. Butter, NOT LARD (yuck), & NO FINGERS!! Cold butter, pastry blender or food processor, like piecrust (you have that in UK, yeah?) Dry ingredients and butter should look like very coarse meal. Make drop biscuits - use a bit more milk (whole milk, no cream), mix til combined, but no more, drop by .25 cop measure onto greased baking sheet. Goal is no handle dough as little as possible, makes for tender, flaky biscuits.
Sausage gravy is best made from a spicy hot sage sausage. I use a brand called "Old Folks" which barely renders enough fat for gravy. This is a feature, not a bug. Brown sausage in a dry pan, remove meat and add flour. You're making a roux, cook flour/fat a while, then use a sauce whisk to begin to incorporate the milk. Keep whisking, bring to simmer, things should thicken. Dump cooked sausage back in, adjust consistency. Adjust seasoning, probably need salt, if you use spicy sausage, you don't need pepper. Biscuits should be broken into chunks on plate, the better to trap and hold gravy ladled over.
Anyone visiting Indiana University, where I wrangle servers and more, I will be happy to clear up the misconceptions about biscuits and gravy. Will admit it looks like concrete chunks in cream sauce. Have seen way too much cat vomit to agree there.