Combine the flour, water, sourdough starter and salt in a bowl and mix with a spatula to incorporate.
When the dough is coming together, melt half of the lard and add it little by little.
Transfer the dough to a well-floured surface and knead for about 3 minutes; the dough should be soft and tacky.
Place the dough ball back in the bowl and cover with cling film. Let rest for 2 hours in a warm place, performing a set of stretch-and-folds after 40 and 80 minutes.
Take the dough out of the bowl and onto your floured working surface. Roll it out and stretch to form a square measuring 35*35 cm (14*14 inches).
Fold the dough in half towards yourself so that the face-up side is now folded inwards.
Cut out the dough every 1-1,5 cm creating thin strips. Take each strip between your fingers and gently pull to double their length, while also lightly twisting them.
Transfer the hand-pulled strips to a sheet pan dusted with cornmeal flour. Melt the rest of the lard and brush it onto the breadsticks. Gently roll each grissini so more cornmeal sticks to its surface.
Bake for 30 minutes in the preheated oven at 200°C (390°F), or 190°C if fan-forced. I recommend to work in batches and turn the tray halfway through the baking time.
Notes
Baking time may vary depending on thickness. Allow a couple more minutes for a deeper golden hue, but do not overbake. The perfect grissini are crunchy and crispy throughout. If some grissini have a softer core leave them out to air dry overnight.Nutrition facts are an estimate and in this recipe they're calculated per piece.