I make the soft-but-crumbly chevre frequently. It is not actually my favorite fresh type, as I like mine a little more stringy and gooey but the following recipe will yield the much more the traditional consistency and flavor which you are asking after - tastes like the long slim logs with the goat on the front that you buy...
This is very popular with friends who add it to salads, pitas, pizza, as a bread spread, sandwiches....on and on.
I use raw goat milk; I assume for past. goat milk you would want to add a bit of CaCl to it...Here's what I do:
1 gal. fresh goat milk
1/4 tsp MM100 meso culture
15 drops Malaka rennet (if you use 20 it will be slightly bitter)
2T un-iodized salt or to taste
opt. sterile herbs for flavor, or garlic or...to your liking
Warm milk to room temp (72F). Dissolve MM culture & rennet into small amount water, and then add this to the tepid milk. Stir gently top to bottom to make sure it is spread throughout. Cover and set aside for 18-24 hours at room temp (around 72-78F - don't do this if your house is 100F inside! - been there, done that. Very Bad!) After 18-24 hours, you will have a firm curd set.
Now gently slice the curd however you like, just to help it release the whey a bit, so it will scoop out neatly. Scoop out into muslin draining cloth (I use old pillowcases, cut and sterilized). Hang the draining bag from a cabinet handle or something with a pot underneath to capture the whey. Drain for roughly 24 hours at moderate room temp, or until it is the consistency you want. Take the bag down, and add the salt, work it in well. If you want to add herbs, now is the time. I generally work in salt, shape it into little balls, and then roll the balls in the herbs. Wrap tightly in plastic, or smoosh into tupperware or however you wish to store it. This should keep in a frig for about 2 weeks - I have a 2 week old batch I had for breakfast this morning...
I think it is the MM100 culture which lends this the authentic texture and taste. I also do this with buttermilk, but that yields a soft, gooey, stringy result (my personal fave!). MM100 can be bought at dairy connection, probably lots of other places.
Hope that's what you are looking for!