Fill large/wide shallow pan with water and bring to a boil. You can use a standard saucepan if you don't have a shallow pan big enough to fit spaghetti, but don't use too much water here - we want the water to get starchy. Once boiling add 2 large pinches of salt and spaghetti.

Heat medium saute pan (i'm using a 10") over medium high heat. Add oil and black pepper. Shake to combine and fry pepper in oil for about 30 seconds. When beginning to take on color, remove heat from pan.

When pasta is cooked to al dente, use tongs to transfer spaghetti into pan with pepper/oil along with about 60g/2oz pasta water - again, we're still off heat. Add in 15g (or half) of the cold butter and swirl and toss in while butter melts. Once the butter is emulsified, add the remaining 15g butter. Swirl and toss until emulsified. Sauce should be opaque and unbroken. If sauce looks tight, add more pasta water (I added 30g/1oz) and toss to combine, switching to tongs to finish tossing and incorporating when sauce begins to thicken. Add another splash of pasta water if needed (30g/1oz or so). If cheese isn't completely melted, place pan over lowest heat for only about 15 seconds or until cheese is just melted, continuing to stir/toss. Plate up and top with grated parm and cracked black pepper.

Add water to a high sided container. With immersion blender spinning, add xanthan gum to water.

Fill large deep pot with water (i'm using my 6.75qt dutch oven) and bring to boil. Once boiling, add 3 large pinches of salt - water should be very salty. Add in pasta and stir.

When pasta is about halfway cooked, preheat a saute pan over med-high. Add olive oil and black pepper. Shake to combine and allow to fry and bloom for about 30 seconds. Once pepper is beginning to take on some color, add xanthan gum slurry and whisk to combine. Reduce heat to medium low. Add 60g or ½ of the cold butter. Whisk to combine, stirring constantly. Add remaining 60g butter and continue whisking constantly until fully emulsified. Reduce heat to low while pasta finishes cooking.

When pasta is cooked to al dente, reserve at least 150g/6oz pasta water. Drain off pasta then return noodles to cooking vessel. Off heat, add the pepper/butter/oil sauce and 150g reserved pasta water to the noodles. Stir to combine. Add pecorino. Stir to combine and melt into sauce. Very briefly add low heat if needed, to finish melting the cheese. Off heat, add parmesan and stir until creamy. Taste for seasoning. Add pinch of salt and additional cheese if needed/desired. Garnish with fresh cracked black pepper and additional parm.